Final answer:
The main function of pedicellariae is for cleaning, helping to keep the echinoderm's body free from debris and parasites, which is different from the locomotor functions provided by cilia, pseudopodia, and flagella in protists and the complex movements of rotifers. The correct option is (3).
Step-by-step explanation:
The question poses an inquiry into the main function of pedicellariae. Pedicellariae are small pincer-like appendages found on some echinoderms, such as sea stars and sea urchins. Unlike the locomotor mechanisms described in your provided information, such as cilia, pseudopodia, and flagella used by various protists to move, and the rotifers' and other animals' methods of locomotion, pedicellariae serve a different function.
The primary role of pedicellariae is cleaning, as they help the organism by removing debris, deterring predators, and controlling the growth of organisms such as algae on the echinoderm's body. Therefore, the correct answer to the function of pedicellariae is (3) cleaning.