KVPY 2019 SB SX Exam Previous Papers

In a population NAA and Naa are the number of homoxygous individuls of allele 'A' and 'a', respectively, and NAa is the number of heteroxygous individuals. Which one of the following options is the allele frequency of 'A' and 'a' in a population with ${\mathit{N}}_{\mathrm{AA}}=90,{\mathit{N}}_{\mathrm{Aa}}=40$ and ${\mathit{N}}_{\mathrm{aa}}=70$?