An analyst estimates the index model for a stock using regression analysis involving total returns, not the excess return. The estimated intercept in the regression equation is $6\%$ and the $$ is $0\mathrm{.}5.$ The risk$-$free rate of return is $12\%.$ The true $$ of the stock is

A$.0\%$

B$.3\%$

C$.6\%$

D$.9\%$