Concept: This question tests your knowledge of the sensory organs found in lower invertebrates, specifically Planaria, and their functions.

Why (A) is correct: Planaria, a type of flatworm, possess specialized sensory structures to interact with their surroundings. Ocelli (simple eyespots) are light-sensitive organs that help them detect light intensity and direction, though they don't form images. Auricles are chemosensory lobes located on the sides of the head that help them detect chemicals in the water, aiding in food location and navigation.

Why other options are wrong:

(B) Flame cells: Flame cells are part of the excretory system (protonephridia) in Planaria, involved in osmoregulation and waste removal, not sensory perception.

(C) Genital pores: Genital pores are openings for the reproductive system, used for copulation and egg release, not sensory perception.

(D) Both A and B: While option A is correct, option B (Flame cells) is incorrect as they are excretory, not sensory structures.

Common Mistake: Students often confuse excretory structures like flame cells with sensory organs, or reproductive structures with sensory functions.

NEET Tip: Remember that even simple organisms have specialized structures for essential functions. For Planaria, think 'Eyes and Ears' (Ocelli and Auricles) for sensing, and 'Flame' for excretion.

Correct Answer: (A)