For semester exam preparation, consider this situation: an elongated soft-bodied echinoderm lies on the sea floor and has reduced ossicles. The correct conclusion is:

Correct Answer: C

sea cucumbers

Sea cucumbers belong to Holothuroidea. They are elongated echinoderms with leathery bodies and reduced skeletal ossicles compared with sea urchins. This MCQ belongs to the Holothuroidea topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.