The foreign institutional investors (FIIs) were net buyers to the tune of Rs 1,914.56 crore in the futures & option segment on Monday.According to data released on the NSE website, FIIs were net sellers of index futures to the tune of Rs 152.62 crore, while they sold index options worth Rs 76.50 crore. They were net buyers of stock futures to the tune of Rs 2,140.91 crore and they bought stock options worth Rs 2.78 crore.As per data available on the Sebi website - FIIs were net sellers of stocks worth Rs 1,361.30 crore in the spot market on the Friday. Domestic mutual funds (MFs) were net buyers of shares worth Rs 848.35 crore on the same day.