The A¹ allele Mutates into the A² Allele at a Rate

Multiple Choice

The A¹ allele mutates into the A² allele at a rate of 4 × 10^-5 and the A² allele mutates into the A¹ allele at a rate of 1 × 10^-5. Assuming no other evolutionary forces are at work, the frequency of the A² allele will eventually be:

A) 0.8.
B) 0.2.
C) 0.5.
D) 0.25.
E) 1.0.