By Mike Yamamoto, managing editor of OptionMonsterNEW YORK -- Housing stocks have been trying to rebound in the last week, and Wednesday the bulls piled into homebuilder MDC Holdings ( MDC). OptionMonster's tracking systems detected upside option activity in the October 30 calls, where nearly 2,700 contracts traded for $1.15 to $1.75. The volume was well above the strike's previous open interest of 417 contracts, indicating that new positions were established. These calls lock in the price where shares can be purchased, letting investors benefit from gains in MDC for much less capital than buying the stock directly. The options can also provide significant leverage in a rally, but they will expire worthless if shares remain below $30 through mid-October. MDC rose 2.36% to $29.97 Wednesday, heading back toward its 50-day moving average after a three-month selloff between June and August. Other homebuilders and related names have seen bullish option action this week, including KB Home, Lowe's, and Mohawk Industries. Total option volume in MDC was five times greater than average Wednesday, with calls outnumbering puts by 26 to 1. Yamamoto has no positions in MDC.