Detailed Explanation:

Fungi are heterotrophic organisms that lack chlorophyll, the pigment essential for photosynthesis. Without chlorophyll, they cannot synthesize their own food from sunlight and must absorb nutrients from organic matter in their environment.

They require oxygen (most are aerobic), utilize carbon dioxide in respiration, and grow in various light conditions—thus these components are not lacking. Their cell walls contain chitin, distinguishing them from true plants.

Therefore, chlorophyll is the key component fungi lack, making Option 2 the correct answer.