Final answer:
Since momentum is the product of mass and velocity, and the mass of the basketball is three times that of the softball with both moving at the same speed, the basketball has a greater momentum.
Step-by-step explanation:
The question is asking us to compare the momentum of a basketball and a softball when they are moving at the same speed. Momentum is defined as the product of an object's mass and velocity (p = mv). If the mass of the basketball is three times greater than that of the softball, and both are moving at the same velocity, then by the definition of momentum, the basketball will have three times more momentum. Therefore, the correct answer is: A) The momentum of the basketball is greater.