If you want help me pls Which action had the greatest impact on the success of the rioters in the February Revolution?

Select one:

a) Russian soldiers fired into the crowd, which overwhelmed them with numbers.

b) German nobility supported the rioters because they hated the czar.

c) Russian soldiers turned against their commanding officers and joined the revolution.

d) Germans supported Russian rioters and supported them with armed forces.

I would pick C.

During the February Revolution many armed Russian soldiers turned on their higher up's and started mutinous actions along the Eastern Front. This allowed the revolutionaries to gain more support through man power and more weapons.

(Germany sent Vladimir Lenin back to Russia to cause political unrest but they only transported him back to Russia and funded the Bolsheviks with money not military equipment or troops)

One of the effects of Stalin's Five Year Plans was that "d. Heavy industry expanded", since these plans were meant to quickly industrialize the USSR, which was "behind" the west in this regard.