A radula is a specialized feeding organ used to scrape material off of a substrate for ingestion, much like a cheese grater scrapes shreds off of a block of cheese. Snails, which have this structure, are thus which kind of feeder?

D. mass feeder

Explanation:

A) suspension feeder

B) fluid feeder

C) deposit feeder

D) mass feeder

Suspension feeder requires capturing of food that are suspended in water through the use of specialized organs.

Fluid feeding involves feeding on liquid (such as blood) emanating from other organisms.

Deposit feeding involves feeding on sediments

Mass feeding involves ingestion of scraps of different food materials.

Hence, the correct option is D.