Is my answer right? If not which one is? Thanks!

Answer:
a 2 kg rock with an applied force of 5N.
Explanation:
1) the rule is: a=F/m, where a - acceleration; m - mass, F - force;
2) according to the condition and the rule above the higher acceleration is for 'a 2 kg rock with an applied force of 5N', a=5/2=2.5 [N/kg].