In a population of 2500, how many babies would you expect to have cystic fibrosis, a homozygous recessive condition, if the frequency of the dominant allele is 0.9, and the population is at Hardy- Weinberg equilibrium?
a) 0.9 x 2500 = 2025
b) 2 x 0.9 x 0.1 x 2500 = 800
c) 0.9 x 0.1 x 2500 = 400
d) 0.1 x 0.1 x 2500 = 25