Thermocline exists between hypolimnion and epilimnion.
Reason : Thermocline acts as a barrier between hypolimnion and epilimnion.
Reason : Thermocline acts as a barrier between the two layers.

Options

A. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C. If the assertion is true but the reason is false
D. If both the assertion and reason are false

Answer

A

Explanation

The warner upper part of the lake or epilimnion becomes temporarily isolated from the colder lower water or hypolimnion by a thermocline zone (temperature stratification) that acts as a barrier to exchange of materials. Consequently. The supply of oxygen in the hypolimnion and nutrients in the epilimnion may run short.