Two species of frogs belonging to the same genus occasionally mate, but the offspring fail to develop and hatch. what is the mechanism for keeping the two frog species separate?
a) the postzygotic barrier called hybrid inviability
b) the postzygotic barrier called hybrid breakdown
c) the prezygotic barrier called hybrid sterility
d) gametic isolation

D

Gametic isolation is a type of prezygotic barrier where the gametes (egg and sperm) come into contact, but no fertilization takes place. Gametes may be unable to recognize one another in different species.

answer: 45

explanationyou have to add as well to be it could be

an organism's phenotype is the  form of a trait  that it  displays. for  flowercolor, a pea  plant  can  display  a phenotype of purple or white flowers. an organism's  genotype  is the alleles of a gene it contains. based on his data, mendel concluded that a phenotype can be  determined  by more than one  genotype.