Which is the main reason toads must lay eggs in water?
a. the eggs do not have a shell to prevent water loss.
b. the eggs need to absorb nutrients from water.
c. the eggs are not laid in nests.
d. the eggs need protection from predators.

Whenever diploid populations are in hardy-weinberg equilibrium at a particular locus a) the allele's frequency should not change from one generation to the next, but its representation in homozygous and heterozygous genotypes may change. b) natural selection, gene flow, and genetic drift are acting equally to change an allele's frequency. c) this means that, at this locus, two alleles are present in equal proportions. d) the population itself is not evolving, but individuals within the population may be evolving.