is the cells way of converting food molecules into a form useful to the cell. Photosynthesis?
Cellular respiration?
Osmosis?
Diffusion?

Respiration

Explanation:

cross off Photosynthesis because that is specifically for plants. Diffusion is when molecules move from high concentration to low concentrations. Osmosis helps transport water across the cell.

By process of reduction you can figure it out, but here is what cellular respiration is in it's basics so you can remember in the future. Cellular Respiration is just the process that takes place in cells to convert Chemical Energy from nutrients and turn it into ATP, then releases waste.

well for one plants are always the producer, so a is the answer. a wolf is more of the consumer(predator) and the deer is the prey so i know those two are out of the question. also mushrooms are fungi/fungus so a is the producer.