By Jud Pyle, CFA, chief investment strategist for the Options News NetworkSunTrust Banks ( STI) did not announce any news Thursday to account for its 2% rally, but at least one investor expressed a bullish bet that the stock could climb higher throughout the near-term by buying calls. STI shares closed up roughly 59 cents or more than 2%, to $27.08 without a clear catalyst. The company has not announced its next earnings release date, but analysts anticipate the quarterly report around April 22. More than 10,000 April 29 calls crossed the tape today vs. open interest of 371 contracts, indicating investors traded these options to open. Investors paid the ask price of around $1.31 per contract, meaning call-buyers will make money if STI shares close higher than $30.31 at April options expiration. These calls climbed 3 cents on the day and closed with an implied volatility of 33% compared with a 30-day historical volatility of 38%. Heavy call-buying action like this does not mean investors should run out and buy up STI shares, but at least one investor is willing to pay a relatively high premium to bet on at least 12% of upside in STI throughout the next month. Jud Pyle is the chief investment strategist for Options News Network (www.ONN.tv) and the portfolio manager of TheStreet.com Options Alerts. Click here for a free trial for Options Alerts. Mr. Pyle writes regularly about options investing for TheStreet.com.