A, B, C, D, E and F live on six different floors of the same building. The lowermost floor in the building is numbered 1. the floor above it is numbered 2, and so on till the topmost floor is numbered 6. E lives on the floor immediately below F's floor. D lives on the 2nd floor. C lives on the floor immediately below A's floor. F does not live on the 5th floor. On which floor does B live?
A3rd
B1st
C5th
D6th