In this scenario, the correct answer is option 1: "Momentum of B will be double that of A." Let`s break down the options to understand why this is the correct answer.

Option 1 states that the momentum of B will be double that of A. Momentum is defined as the product of an object`s mass and its velocity. Since the bodies A and B have equal velocities, the only factor that affects their momenta is their mass. As stated in the question, the mass of B is double that of A. Therefore, if the velocity is the same, the momentum of B will indeed be double that of A.

Option 2 states that the momentum of A will be double that of B. However, this is incorrect, as the momentum is directly proportional to the mass. Since the mass of A is lower than that of B, its momentum will be lower as well.

Option 3 states that the momentum of B will be four times that of A. This is also incorrect because the mass ratio between A and B is 1:2. Since momentum is directly proportional to mass, the momentum ratio will also be 1:2.

Option 4 states that the momenta of both A and B will be equal. This is not true