The foreign institutional investors (FIIs) were net buyers to the tune of Rs 305.73 crore in the futures & option segment on Wednesday.According to data released on the NSE website, FIIs were net buyers of index futures to the tune of Rs 260.42 crore while they sold index options worth Rs 21.71 crore. They were net buyers of stock futures to the tune of Rs 67.16 crore while they sold stock options worth Rs 0.15 crore.As per data available on the Sebi website - FIIs were net sellers of stocks worth Rs 111.10 crore in the spot market on Tuesday. Domestic mutual funds (MFs) were net sellers of shares worth Rs 31.32 crore on the same day.