Can someone help me with this please??

Find the volume of a cube on which the diagonal of a face measures 2.

ACUBERT(2)
B8
C12
D2 SQRT(2)
E4
F6 SQRT(2)

let each side have a length of x

then x^2 + x^2 = 2^2
x = √2

now isn't the volume of a cube with side x equal to x^3 ?
so what is (√2)^3 ?

= √2*√2*√2 = 2√2 or √8