31. Phenylketonuria is an autosomal recessive inheritable disease. If the incidence of the disease is about 1/10000, what is the frequency of the phenylketonuria recessive disease allele (a) and the (Aa) genotype frequency of the person carrying the recessive gene in the population?
(A) 0.1% and 0.99%
(B) 0.1% and 1.98%
(C) 1% and 3.96%
(D) 1% and 1.98%
(E) 0.1% and 3.198%