B
Below is a question with multiple-choice answers. Choose the correct option based on your reasoning.

### Question:
All metabolic functions fall into one of two categories: a breaking down process (catabolic) or a building up process (anabolic). Which is an example of an anabolic process?

### Choices:
A. respiration
B. protein synthesis
C. oxygen transport
D. carbohydrate digestion

### Answer:
