As a trader, you would choose to purchase an index call option if you expect the price movement of the index to rise in the near future, rather than that of a particular share. Indices on which you can trade include the CNX Nifty 50, CNX IT and Bank Nifty on the NSE and the 30-share Sensex on the BSE.

The F&O Ban List, also known as the "Futures and Options Ban List," comprises securities that have specific restrictions imposed by stock exchanges. These restrictions prevent excessive speculation or price manipulation in derivative contracts. When a stock is included in the ban list, traders are prohibited from initiating new positions in futures or options contracts of that particular stock.

There are thousands of companies listed on stock markets, making it almost impossible to monitor each company. This is why stock market indices are created.