Let $$L = \left\{\omega \epsilon (0+1)*|  \omega \right\}$$ has even number of 1s, i.e. L is the set of all bit strings with even number of 1s. Which one of the regular expression below represents L?

A

(0*10*1)*

B

0*(10*10*)*

C

0*(10*1*)*0*

D

0*1(10*1)*10*