If the length of a simple pendulum is increased by 4%, then its time period will increase by approximately 2%, which is; option [B]. The time period (T) of a pendulum is directly proportional to the square root of its length (L) as given by the formula, T=2π√(L/g ) where g is the acceleration due to gravity. When the length increases by 4%, the time period increases by approximately 2%. Therefore, option B accurately describes the change in time period resulting from a 4% increase in the length of a simple pendulum, highlighting the proportional relationship between the length and the square root of the time period in pendulum motion.