The closely related,morphologically similar,sympatric populations that are reproductively isolated are designated as

Select the correct match from the following:

Which one of the following is not a living fossil?

Assertion: From an evolutionary point of view,the human gestation period is believed to be shortening.
Reason: One major evolutionary trend in humans has been the larger head undergoing a relatively faster growth rate in the foetal stage.

Identify the correct statement from the given options.

The cause of aging in mammals,including humans,is: