Organisms that can prepare their own food. a. Autotrophsb. Heterotrophsc. Phototrophsd. None of the above

The correct answer is a. Autotrophs.

Explanation: Organisms that can prepare their own food are called autotrophs. These organisms can synthesize their own food from simple inorganic substances like carbon dioxide and water. The process by which they do this is called photosynthesis (in plants, algae, and some bacteria) or chemosynthesis (in some bacteria).

Heterotrophs (option b) are organisms that cannot make their own food and rely on other organisms for nutrition. Examples include animals and fungi.
Phototrophs (option c) are organisms that obtain energy from light, but this term specifically refers to the type of energy source used for metabolism, not the ability to make food. Some phototrophs can be autotrophs, but not all are.
Therefore, the correct answer is a. Autotrophs.