Which macromolecule is the primary energy source for organisms?
question 2 options:
a) sunlight
b) protein
c) fat
d) carbohydrate
e) nucleic acid

The correct option is D.
Carbohydrate is the main energy source for living organism. When carbohydrate food are consumed, the digestive enzymes break the carbohydrate down to glucose. The body cells use glucose as a source of fuel to produce energy which they use for their metabolic activities.

Can you include the paragraph too ?

Dis the