In the following questions , a statement of assertion (A) is followed by a statement of reason (R).
A: In an aquatic ecosystem grazing food chain is the major conduit for energy flow R: Detritus food chain may be connected with the grazing food chain at some levels.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3).
D. If both Assertion and Reason are false statements, then mark (4).