Answer:
Option b
Step-by-step explanation:
The formula of momentum is
![p=mv](https://img.qammunity.org/2021/formulas/physics/high-school/6fwu51bwtbpnbnl3151q1laurhi2qezdog.png)
where p is the momentum , m is the mass in kg and v is the velocity in m/s, so
a) momentum is
![p=mv\\p=5(2)\\p=10](https://img.qammunity.org/2021/formulas/physics/high-school/apjmkzucz0yacvx6t0hk2aaqg106qkp5om.png)
b) momentum is
![p=mv\\p=4(3)\\p=12](https://img.qammunity.org/2021/formulas/physics/high-school/k8uk1ge4vqoj0ap6rvsf8owr0qvaq9lpzg.png)
c) momentum is
here since the rock is sitting on top of a hill which means the object is stationary or in other words the object is at rest, which means if an object is at rest the velocity is 0m/s so momentum is zero of a stationary object because
![p=mv\\p=200(0)\\p=0](https://img.qammunity.org/2021/formulas/physics/high-school/2can3rel3thgcq9wmsr9oisalozyrhh6pi.png)
d) momentum is
![p=mv\\p=0.0025(200)\\p=0.5](https://img.qammunity.org/2021/formulas/physics/high-school/9recd1p9qzs6nj8lelcngs1x8r35gq5rsx.png)
so the highest momentum is in part b which is 12 so option b is our answer.