question_answer

If two sets A and B are having 99 elements in common, then the number of elements common to each of the sets\[A\times B\]and\[B\times A\]are:

A)  \[{{2}^{99}}\]                                   

B)  \[{{99}^{2}}\]

C)  100                       

D)         18

E)  9