Seven boxes J, K, L, M, N, O and P are kept one above

another such that bottommost box is numbered as 1 while the topmost as 7. Box M is prime numbered box above box L, which is 3rd box. There are two boxes between box M and box O. Box J is three boxes above box P. Box N is just above box K. Which of the following is the topmost box?

A L

B J

C K

D N