How do slugs differ from snails in terms of shell presence?

How do slugs differ from snails in terms of shell presence?

• A. Slugs have a coiled external shell
• B. Slugs have a small external shell
• C. Slugs lack a prominent external shell (or have a reduced internal shell)
• D. Snails have no shell

Answer: (C)

Shell presence is the key difference between slugs and snails. Slugs have no prominent external shell, and in many species there’s only a small internal shell vestige. This gives slugs a smooth, soft body that can squeeze into tight spaces. Snails, on the other hand, carry a visible, coiled external shell on their back, which remains a defining feature of their appearance. So the best description is that slugs lack a prominent external shell (or have a reduced internal shell). The other ideas don’t fit because a coiled external shell is typical of snails, and snails do have shells, not no shell.

Shell presence is the key difference between slugs and snails. Slugs have no prominent external shell, and in many species there’s only a small internal shell vestige. This gives slugs a smooth, soft body that can squeeze into tight spaces. Snails, on the other hand, carry a visible, coiled external shell on their back, which remains a defining feature of their appearance. So the best description is that slugs lack a prominent external shell (or have a reduced internal shell). The other ideas don’t fit because a coiled external shell is typical of snails, and snails do have shells, not no shell.