Time taken by boat to cover a distance of x km in upstream is 3 hours more than the time taken by the boat to cover the same distance to downstream. Speed of the boat in upstream is 8 km/hr. Which of the following statement(s) is/are correct?

I. If the value of x is 48 km, then speed of boat in downstream is 16km/hr.
II. If the speed of boat in downstream is 12 km/hr, then the value of x is 48 km.

A

Neither I nor II

B

Only II

C

Only I

D

Both I and II