Concept: This question tests your understanding of the evolution and complexity of the neural system across different invertebrate phyla, specifically comparing cnidarians (Hydra) and arthropods (insects).

Why (B) is correct:

Statement I is incorrect because the neural system in insects is far more complex and better organized than in Hydra. Hydra, a cnidarian, has a very primitive, diffuse nerve net without a centralized brain or ganglia. Insects, being arthropods, possess a well-developed neural system with a centralized brain, a ventral nerve cord, and numerous ganglia, allowing for more complex behaviors.

Statement II is correct. The neural system of insects is indeed characterized by a centralized brain (supraesophageal ganglion), a ventral nerve cord, and segmental ganglia, along with various neural tissues, which represents a significant evolutionary advancement over the nerve net of cnidarians.

Why other options are wrong:

A) Statement I is incorrect, making this option wrong.

C) Statement I is incorrect, making this option wrong.

D) Statement I is incorrect, but Statement II is correct, so this option is wrong.

Common Mistake: Students might underestimate the complexity of insect nervous systems or overestimate the organization in simpler organisms like Hydra.

NEET Tip / Mnemonic: Remember the evolutionary trend: Nerve net (Cnidarians) → Ganglia (Platyhelminthes) → Segmented ganglia + ventral nerve cord (Annelids, Arthropods) → Centralized brain + dorsal nerve cord (Vertebrates).

Correct Answer: (B)