The correct answer is B. Photosynthesis.
Photosynthesis is the process by which plants use sunlight to create food. Animals, on the other hand, cannot photosynthesize. They must consume food that has already been created by plants or other organisms.
Respiration is the process by which organisms break down food molecules to release energy. This process is essential for all living things, including animals.
Reproduction is the process by which organisms create new individuals. This process is also essential for all living things, including animals.
Digestion is the process by which organisms break down food into smaller molecules that can be absorbed by the body. This process is essential for all living things, including animals.
In conclusion, the only process that cannot be performed by animals is photosynthesis.