Given below are a few statements related to exgternal fertilisation. Choose the correct statements.
(i) The male and female gametes are formed and released simultaneously.
(ii) Only a few gametes are released into the medium.
(iii) Water is the medium in a majority of organisms exhibiting external fertilisation.
(iv) Offspring formed as a result of external fertilisation have better chance of survival than thos formed inside an organism.

Options

A. III and IV
B. I and III
C. II and IV
D. I and IV

Answer

B

Explanation

External fertilisation occurs outside the body of the organism. It takes place in most aquatic organisms, such as a majority of algae and fishes as well as amphibians. Organisms exhibiting external fertilisation release a large number of gametes in the surrounding medium. (e.g., water) in order to enhance the chances of syngamy.
A major disadvantage is that the offspring are extremely vulnerable to predators threatening their upto adulthood.