Why Did Stalin Stop Soviet Troops from Coming to the Aid

Why did Stalin stop Soviet troops from coming to the aid of the Warsaw Uprising in 1944?

A) He wanted the Polish government in exile to be weak in order to make the Soviet occupation of Poland easier.
B) He told his generals that the uprising was being led by kulaks and therefore was anti-revolutionary.
C) He had to divert units south to stop a German advance through the Ukraine.
D) The United States asked him to stop so resources could be diverted for D-Day.
E) Winter was approaching and Soviet tanks had to be retrofitted for the advance into Germany.