Answer:
the covariance between the security's return and the market return divided by the variance of the market's returns
Step-by-step explanation:
The market risk, beta of the security would be equivalent to the
Beta = Cov(rm, rs) รท Var(rm)
Rm denotes market return
rs denotes security return
Cov denotes covariance
Var denotes variance
Hence, the second option is correct
And, the rest of the options are wrong