A diagram in the course handout shows that oysters and mussels are discussed in a practical note on useful invertebrates. Identify the related structure or process.

Correct Answer: B

economic value as food and pearls

Molluscs have economic importance as food sources and in pearl production. Some species are also intermediate hosts of parasites or pests, so their impact can be both beneficial and harmful. This MCQ belongs to the Mollusca topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.