Final answer:
The mass of the pendulum does not affect its period. Therefore, the new period will be the same as the original period. The correct option is B).
Step-by-step explanation:
The period of a simple pendulum is determined by its length and the acceleration due to gravity. The formula for the period of a pendulum is T = 2π√(L/g), where T is the period, L is the length of the pendulum, and g is the acceleration due to gravity.
If the mass of the pendulum is replaced by a mass of 2M, the period of the pendulum remains the same because the formula for period does not depend on the mass of the pendulum.
Therefore, the answer is B) T. The new period will be the same as the original period.