Assertion (A) : Methane is called marsh gas.
Reason (R) : Decomposition of plant and animal matter in am oxygen deficient environment like swamps, mashes and bogs produce methane gas.
(a) Both (A) and (R) are correct and (R) is the correct explanation of (A).
(b) Both (A) and (R) are correct but (R) is not the correct explanation of (A).
(c) (A) is correct but (R) is wrong.
(d) (A) is wrong but (R) is correct.