A 36.9 kg girl and a 60.0 kg boy are on a frozen lake, 13.5 m apart. The girl exerts a horizontal 4.80 N force on the boy, pulling him toward her. What is the magnitude of the force exerted by the girl on the boy?

A) 4.80 N
B) 13.5 m
C) 97.8 N
D) 60.0 kg