Question

Phylum Mollusca can be distinguished from other invertebrates by the presence of

• A. Bilateral symmetry and exoskeleton
• B. A mantle and gills
• C. Shell and segmented body
• D. A mantle and non-segmented body

Answer 1

The correct option is D A mantle and non-segmented body

• In phylum Mollusca, an animal's body is covered by a calcareous shell as an exoskeleton and is unsegmented with a distinct head, muscular foot, and visceral hump.
• The skin has a soft and spongy layer that forms a mantle over the visceral hump.
• They are bilaterally symmetrical, like other invertebrates (arthropods, annelids).

Thus, the correct answer is option D.