Final answer:
A vegan is an individual who abstains from consuming any animal products and must strategically combine plant-based proteins to fulfill their nutritional requirements for essential amino acids.
Step-by-step explanation:
The term for a strict vegetarian who will not eat meat, fish, poultry, or any products derived from animals is d. vegan. Vegans need to pay special attention to the protein they eat because b. It is more difficult to obtain all essential amino acids from single plant sources. Unlike animal proteins, which are complete, most plant sources do not provide all the essential amino acids in one food. Therefore, vegans must consume a variety of plant-based proteins to ensure they're getting all the essential amino acids their cells need to grow and function properly. This can be achieved through proper meal planning and by combining different plant-based protein sources throughout the day.