Several narrowly focused exchange-traded funds were at the top of their class in April.

The broadly diversified market inched ahead in the month. The small-capitalization stocks of the Russell 2000 Index gained 4.19%. The large-cap

S&P 500

index did a bit better at 4.87%.

The best-performing ETF in the month was

B2B Internet HOLDRs Trust

(BHH)

, up 29.73% from March 31 to April 30. The turnaround in performance led to an upgrade in the rating of this fund to C-, Hold, from E-, Sell.

The fund is so narrowly focused to U.S. B2B Internet companies that it has only two holdings, with an allocation of 85.7%

Ariba

(ARBA)

and 14.3%

Internet Capital Group

(ICGE)

.

If two holdings is one too many for you, the B+ rated

MACROshares Oil Up

(UCR)

needed only one target to return 25.39% in April.

As billions of people around to world strive to improve their standard of living, aggregate demand for oil is not likely to significantly abate even during a U.S. recession. This fund's second-place performance is a symptom of that phenomenon.

Two other energy funds,

ProShares Ultra Oil & Gas

(DIG) - Get Report

, up 21.76%, and

Market Vectors Coal ETF

(KOL) - Get Report

, up 16.41%, benefited from this trend.

Honorable mention goes to Brazil, China, and India, which captured five of the 10 spots on our list of best-performing ETFs.

It's no wonder that these are the same countries where foreign direct investment helped spark business activity, the accumulation of private wealth, increased local consumer demand and the prosperity of some of their largest publicly traded companies.

With returns of 17.97% and 17.25% in April,

SPDR S&P China ETF

(GXC) - Get Report

and

iShares MSCI Brazil

(EWZ) - Get Report

represent pure plays.

If you're looking for an ETF that covers all three countries, check out the

Claymore/BNY BRIC ETF

(EEB) - Get Report

. This A+ rated ETF has restricted investments in Russia to 4.3% of its assets, because any commercial success faces the renewed risk of nationalization.

For an explanation of our ratings,

click here

.

Kevin Baker became the senior financial analyst for TSC Ratings upon the August 2006 acquisition of Weiss Ratings by TheStreet.com, covering mutual funds. He joined the Weiss Group in 1997 as a banking and brokerage analyst. In 1999, he created the Weiss Group's first ratings to gauge the level of risk in U.S. equities. Baker received a B.S. degree in management from Rensselaer Polytechnic Institute and an M.B.A. with a finance specialization from Nova Southeastern University.