If x,y are numbers >0 and 2^x*5^y=400

If x,y are numbers >0 and 2^x*5^y=400, what could be the value of x?

I)2
II)3
III)4

A)Only I
B)Only II
C)I and II
D)Only III
E)I, II and III

Hi guys, this is my first PS question hope you like it, any feedback is appreciated.

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