Foreign institutional investors (FIIs) were net sellers of Rs 3,760 crore in the futures & options (F&O) market on Wednesday, January 16.FIIs were net sellers of Rs 3,164 crore in index futures, and Rs 1,080 crore in stock futures. They were buyers of Rs 484 crore in index options.FIIs were net sellers of Rs 2,517.59 crore (provisional) in the cash market on Wednesday, according to data released by BSE. While they made gross purchases of Rs 4,439.43 crore, gross sales totalled Rs 6,957.02 crore.Domestic institutional investors (DIIs) were net buyers of Rs 188.97 crore on Wednesday. While they made gross purchases of Rs 1,864.99 crore, gross sales totalled Rs 1,676.02 crore.FIIs were net buyers of Rs 225.80 crore on Tuesday, January 15, according to data released by Sebi. While FIIs made gross purchases of Rs 5,209.90 crore, gross sales totalled Rs 4,984.10 crore.Mutual funds (MFs) were net sellers of Rs 519.50 crore on Tuesday. MFs made purchases of Rs 573.10 crore and sales of Rs 1,092.50 crore.