Which of the following statements is FALSE?

a$.$ Because investors are risk averse, they will demand a risk premium to hold unsystematic risk.

b$.$ Because investors can eliminate firm$-$specific risk "for free" by diversifying their portfolios, they will not require a reward or risk premium for holding it$.$

c$.$ Over any given period, the risk of holding a stock is that the dividends plus the final stock price will be higher or lower than expected, which makes the realized return risky.

d$.$ The risk premium for diversifiable risk is zero, so investors are not compensated for holding firm$-$specific risk.