What are three methods used to shift the center of gravity (CG) of a rocket forward?

Shifting the center of gravity (CG) of a rocket forward is essential for achieving stability during flight. When the CG is located forward, it helps maintain stable flight characteristics by ensuring that aerodynamic forces act effectively to control the rocket's trajectory.

Adding weight to the nose of the rocket is a direct and effective method to move the CG forward. This added weight changes the distribution of mass, bringing the CG closer to the front of the rocket. Making the rocket longer can also contribute to this adjustment because it generally means that additional mass can be positioned further forward, again helping to shift the CG. Additionally, using a smaller or lighter motor reduces the weight of the tail section, which can help balance the rocket and further push the CG forward as the mass distribution shifts.

This reasoning clarifies why the methods outlined in the correct option effectively move the CG forward. The other options do not accurately achieve this goal or risk compromising the rocket's stability.