Correct option is D
Given:
All are facing into North.
Only one person is sitting between C and R.
Only one person is sitting to the left of C.
Only two people are sitting to the right of F.
R is sitting to the immediate left of F.
According to the given information seating arrangements will be:

As per the diagram, there are 7 people sitting in the row.
Thus, the correct option is (d)