Diversification is the only free lunch in this business, Jim Cramer reminded his Mad Money viewers Wednesday, as the fast-growing tech stocks got slammed, but the retail and transports rallied big.

There's not a lot of new money entering the stock market these days, which means that money managers are forced to sell something when they decide to buy something new. That's how red-hot tech stocks like Facebook (FB) , were down 4%, Amazon (AMZN) , off 2.7% and Netflix (NFLX) , lost 5.5%.

Why buy the beaten-down retailers and transports? They're among the biggest beneficiaries of the Republican tax reform plan, which looks as if it might actually have a chance of making it through Congress.

Also read: What should we expect after Wednesday's big slide on the Nasdaq? Turns out the Nasdaq has seen little follow through on its big down days so far in 2017.

Cramer recalled that 15 years ago, as the dot-com stocks imploded, diversification was the only thing that saved investors.

He's taken that lesson to heart and has preached the importance of diversification ever since. New investors should begin with a low-cost index fund that has diversification built-in, before buying any individual names.

The key to investing is staying in the game, Cramer concluded, and that's hard to do when you get blown out by a single sector in single day. Today was the beginning of a buying opportunity, but only for those who have money left to take advantage of it.

Executive Decision: PVH Corp.

For his "Executive Decision" segment, Cramer again sat down with Manny Chirico, chairman and CEO of PVH Corp.  (PVH) , the apparel maker with shares that are up 51% so far this year, thanks in part to an 11-cents-a-share earnings beat reported earlier Wednesday.

Chirico said he's seen a "big change" in the domestic market over the past six weeks. He said retailers across the board are seeing strong sales and it's shaping up to be the strongest holiday season in at least the past four years.

That's part of the reason PVH has been thoughtfully buying back shares of their own stock, Chirico said. A few months ago, the price of the stock was out of alignment with the momentum they were seeing.

Will tax reforms make retail even stronger? Chirico said that while tax cuts will likely help his industry, he's disappointed that a middle-class tax cut, as it was originally billed, has failed to materialize.

Cramer and the AAP are continuing the theme of selling names into the strength of today's rotation. Find out what they're telling their investment club members about Nucor (NUE) and more, and get in on the conversation with a free trial subscription to Action Alerts PLUS.

Time Will Tell With StitchFix 

The stock of StitchFix (SFIX) may have caught fire since its IPO last week, but there's too much uncertainty for the company to make it onto Cramer's holiday shopping list.

Cramer said that the StitchFix story is intriguing, as the company blends hard data science with a human touch to deliver customers with boxes of apparel they love. The company has 3,400 personal stylists coupled with 75 data scientists and its 2.2 million active customers have an 86% repeat purchase rate.

But after growing 113% in 2016, StitchFix has seen its growth slow to just 38%, with gross margins also beginning to decline. After becoming profitable last year, StitchFix has also slipped back into the red as it invests heavily to reinvigorate that growth.

At the end of the day, investing is always about the numbers, Cramer reminded viewers. Money managers always look for accelerating growth, not declining growth, and that makes StitchFix too risky until it can prove its business model can stabilize.

No-Huddle Offense

In his "No-Huddle Offense" segment, Cramer pondered just how much importance investors should be placing on the millennial generation. While the millennials and the still younger post-millennials, are an enigma to most money managers, the group now accounts for the largest segment of the American consumer.

So when Cramer proclaimed on Tuesday night's show that the millennials prefer to get their protein from chicken, there was a lot of eye rolling. But how else do you explain the strength in Tyson Foods (TSN) , our nation's largest chicken provider, and the recent acquisitions of Popeye's Louisiana Kitchen and Buffalo Wild Wings (BWLD) by firms with long histories serving beef?

The evidence doesn't lie, Cramer proclaimed, which is why he's also bullish on Thor Industries (THO) , which is seeing secular growth thanks to a resurgence of millennial buyers.

Over on Real Money, Cramer asks, "Do I make too much of millennials?" Probably not. Get more on his insights with a free trial subscription to Real Money. 

Lightning Round

In the Lightning Round, Cramer was bullish on Tower Semiconductor (TSEM) .

Cramer was bearish on Momo (MOMO) , New Residential Investment (NRZ) and Netease (NTES) .

Executive Decision: CBRE Group

In his second "Executive Decision" segment, Cramer sat down with Bob Sulentic, president and CEO of CBRE Group (CBG) , a stock that's up 12% since Cramer last checked in four months ago.

Sulentic explained that corporations are their biggest clients, so if those companies have more money to invest after tax reforms, then they'll be growing and moving, both of which are great for CBRE.

CBRE recently closed a $1.5 billion fund to invest in more real estate to help meet that anticipated demand.

When asked about the trend toward co-working spaces, Sulentic said that co-working companies will take big spaces and lease them out in smaller chunks, and CBRE often assists them in doing so. In some cases however, they do compete with co-working. He said the trend is "very real" and will likely continue to grow.

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At the time of publication, Cramer's Action Alerts PLUS had a position in NUE, FB.

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