By Jon "DRJ" Najarian, co-founder of OptionMonster Options trading is bullish in Fluor ( FLR) as its shares continue a sharp rebound. The engineering company's average daily call volume has been 4,900 in the last month, but nearly 15,000 had changed hands Thursday by mid-afternoon. One trade alone -- a July 45-55 bullish spread -- moved 5,000 calls at each leg, according to OptionMonster's tracking systems. Fluor shares closed Thursday up 8.9% to $40.42 on heavy volume. Fluor had fallen sharply since trading near $50 at the beginning of the year to around $30 earlier this month, but it has risen more than 33% in the last eight trading days alone.