A diagram in the course handout shows that a marine worm releases gametes into water and produces swimming larvae. Identify the related structure or process.

Correct Answer: D

separate sexes and external fertilization often occur

Many polychaetes have separate sexes and external fertilization, often producing trochophore larvae. This contrasts with many oligochaetes, which are hermaphroditic. This MCQ belongs to the Polychaeta topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.