What number must be multiplied to 6912, so that the product becomes a perfect cube?
Prime factorising 6912, we get,
6912=2×2×2×2×2×2×2×2×3×3×3
=28×33.
We know, a perfect cube has multiples of 3 as powers of prime factors.
Here, number of 2's is 8 and number of 3's is 3.
So we need to multiply another 2 to the factorization to make 6912 a perfect cube.
Hence, the smallest number by which 6912 must be multiplied to obtain a perfect cube is 2.
Hence, option A is correct.