The correct option is C 10 gm mass
case1:m1=10g=0.01kg;
a1=5ms−2
now,
F1=m1a1=0.01×5
F1=0.05N
case2:m2=20g=0.02kg
a2=2ms−2
so,
F2=m2a2=0.02×2
or F2=0.04 N
We find that F1>F2, hence more force is required to accelerate a 10 g mass at 5ms−2, than accelerating a 20 g mass at 2ms−2.