In close comparisons, extemal fertilization often yields more offspring than internal fertilization. However,
internal fertilization offers the advantage that
a. it requires less time and energy to be devoted to reproduction
b.
the smaller number of offspring produced often receive a greater amount of parental care
and thus have a greater survival rate.
c. it requires expression of fewer genes and maximizes genetic stability,
d. it is the only way to ensure the survival of species