A swing playing with small amplitude can be considered as a simple pendulum. Such a swing is set to oscillate with an amplitude $$a$$ and frequency $$f$$. When it is at its mean position, a box of same mass as that of the seat of the swing is dropped on it and it starts moving with the swing. Choose the correct statement.

A

Amplitude is reduced to half its initial value and frequency is doubled

B

Amplitude is reduced to half its initial value and frequency is unchanged

C

Amplitude doubles and frequency is unchanged

D

Amplitude remains same and frequency is half its initial value