The Foreign Institutional Investors (FIIs) were net sellers to the tune of Rs 251.46 crore in the futures & options segment on Monday.According to data released by the NSE, FIIs were net sellers of index futures to the tune of Rs 46.62 crore and bought index options worth Rs 60.90 crore. They were net sellers of stock futures to the tune of Rs 247.54 crore and sold stock options worth Rs 18.20 crore.