Assertion : Moulting or ecdysis occurs only in invertebrates.
Reason : In birds, moulting ususally taken an average time of six weeks.

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 the assertion is false but reason is true

Answer

D

Explanation

Moulting or ecdysis occurs not only in invertebrates, but in birds also. In birds, shedding and replacement of feathers is moulting or ecdysis which takes place gradually, moulting usually takes an average time of six weeks. At the base of each feather follicle, a dermal papilla persists form which new feathers will form. Thus there is a continuous replacement of feather throughout life. The replacement of feathers is seasonal in some birds such as pigeon it is gradual throughout the year.