(A) : Mycorrhizae represent an intimate mutualistic relation between a fungus and algae.
(R) : The fungi provides the energy yielding carbohydrates.
A. If both (A) and (R) are true but (R) is not the correct explanation of (A).
B. If both (A) and (R) are true and (R) is the correct explanation of (A).
C. If (A) is true but (R) is false.
D. If both (A) and (R) are false.