The standard deviation of Y is double of standard deviation of X. The correlation coefficient between X and Y is 0.5. The acme angle between lines of regression is

A

arctan $$\left(\frac{4}{5}\right)$$

B

arctan $$\left(\frac{3}{5}\right)$$

C

arctan $$\left(\frac{1}{5}\right)$$

D

arctan $$\left(\frac{2}{5}\right)$$