Answer: B. It is directed to the left.
Step-by-step explanation:
Gravitational force is an attractive force, this is stated by Newton's law of Gravitation:
"The force exerted between two bodies of masses m1 and m2 and separated by a distance is equal to the product of their masses and inversely proportional to the square of the distance"
This means both m1 and m2 are mutually attracted.
Hence, if the force exerted on m1 by m2 is directed to the right, the force exerted on m2 by m1 must be logically directed to the left.