Which of the following animals can regenerate arms and parts of the body?
(a) Star fish
(b) Brittle star
(c) Sea lily
(d) Aves

The correct option is B a, b and c
Many animals can regenerate, that is, regrow or grow new parts of their bodies to replace those that have been damaged. Echinoderms can regenerate missing limbs, arms, spines and even intestines (for example sea cucumbers). Some brittle stars and sea stars can reproduce asexually by breaking a ray or arm or by deliberately splitting the body in half. Each half then becomes a whole new animal. Planarians are flatworms when cut into pieces, each piece can grow into a new worm. Sea cucumbers have bodies that can grow to be three feet long and shows the phenomena of regeneration. Spiders can regrow missing legs or parts of legs. Sponges can be divided. The cells of the sponge will regrow and combine exactly as before. Starfish that lose arms can grow new ones, sometimes an entire animal can grow from a single lost arm. Birds (Aves) on the other hand, do not have this ability

Therefore, the correct answer is option A.