If You Use Index Calls to Generate Additional Income in a Stock

If you use index calls to generate additional income in a stock portfolio, which of the following statements is true?

A) Regardless of the portfolio size, the income that can be generated with index calls is fixed and known
B) The higher the striking price, the greater the number of options you can write
C) The lower the striking price, the greater the number of options you can write
D) Writing index options eliminates the downside risk of a portfolio