Willow Company's employees work Monday-Friday, receive paid holidays, never earn overtime, and are paid $3,000 (in total) every other Friday.

 Willow Company's employees work Monday-Friday, receive paid holidays, never earn overtime, and are paid $3,000 (in total) every other Friday. Willow makes the following entry on the first Friday payday in January:

Consider the above information, on what day of the week did December 31st fall?

A) Monday

B) Tuesday

C) Wednesday

D) Thursday

E) Friday 

please explain it.