The correct option is B 4200
Frequency of recessive allele (q) = 0.4
Frequency of dominant allele (p) = 1-.4=0.6
Hence, dominant individuals would be = homozygous + heterozygous =2pq+p2
=(2×0.4×0.6)+(0.6×0.6)
= 0.48 + 0.36
= 0.84 = 84%
So, dominant individuals in a population of 5000 = 0.84 X 5000 = 4200.