What are the frequencies of the a and a alleles

If the frequency of aa genotype is 0.16, the frequency of Aa genotype is 0.48, and the frequency of AA genotype is 0.36 what are the frequencies of the A and a alleles?

A) 0.7, 0.3
B) 0.3, 0.7
C) 0.6, 0.4
D) 0.15, 0.85
E) 0.85, 0.15