If a stock return is expected to be the same as the expected return on the market, the stock’s CAPM beta is? and how do you know?

If a stock return is expected to be the same as the expected return on the market, the stock’s CAPM beta is? and how do you know?

a. 0.0

b. 0.5

c. 1.0

d. Undefined

If a stock return is expected to be the same as the expected return on the market, the stock’s CAPM beta is? and how do you know?