Consider a 4-PSK constellation with points $$\left\{\sqrt{2}, j\sqrt{2}, -\sqrt{2}, -j\sqrt{2}\right\}$$ and a 4-PAM constellation {-3, -1, 1, 3}. If all the points in the constellation occur with equal probability, the ratio of average energy of 4-PAM signal to that of 4-PSK signal is:

A

1

B

1.25

C

2.5

D

5