Question

Regarding assertion and reason, choose the correct option_______.
Assertion [A]: Cold air causes vasodilation of blood vessels in the nasal cavity.

Reason [R]: Oxygen can be absorbed by widened blood vessels.

• A. Assertion [A] is True and Reason [R] is False.
• B. Reason [R] is True and Assertion [A] is False.
• C. Assertion [A] is True and Reason [R] is True and is a correct explanation to [A].
• D. Assertion [A] is True and Reason [R] is True but is not a correct explanation to [A].

Answer 1

The correct option is A

Assertion [A] is True and Reason [R] is False.

Warming of the air is important because cilia are very sensitive to temperature, and also because breathing in of cold air can cause loss of heat from the body's internal surfaces. Colder air causes vasodilation of the blood vessels, so that more blood can flow into warm the air.