Assertion : Bones possess longitudinal canals called lacunae.
Reason : Lacunae carry blood vessels & nerves to the bones.

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 and reason are false
D. If the assertion is false but reason is true

Answer

D

Explanation

Lacunae are actually the falt irregular spaces occurring in the solid matrix of bone. Each lacuna lodges a flat bone cell or osteocyte. Compact bone possesses many parallel, longitudinal column like structures called haversian systems in which several concentric layers of bony matrix called lamellae encircle a longitudinal centeral canal called haversian canal. It is the Haversian canal which carries blood vessels and nerves to the bone. Lacunae containing osteocytes occure in a layer betweet two lamellae.