Choose the correct one with respect to external fertilisation in organisms.

detailed solution

Correct option is D

In external fertilization there must be synchrony between the release of male and female gametes.External fertilization is commonly observed in majority of algae and fishes as well as amphibians. A majority of plants (bryophytes, pteridophytes, gymnosperms and angiosperms), syngamy occurs inside the body of the organism, hence the process is called internal fertilisation.External fertilization happens in the bony fishes and frogs where many offspring are produced. A major disadvantage is that the offspring are extremely vulnerable to predators threatening their survival up to adulthood.