Which of the following sentences is punctuated correctly?

Question

a

My appointment with Dr. Nayel is at 5:15 PM
b

My appointment with Dr. Nayel is at 5:15 PM.
c

My appointment with Dr. Nayel is at 5:15 P.M.
d

My appointment with Dr Nayel is at 5:15 P.M.

Answer 1

b

My appointment with Dr. Nayel is at 5:15 PM.