Analogy — Preserve opposition of states: A : Inert :: Active : B

Introduction / Context:
“Inert” contrasts with “active.” The most direct lexical opposites are “static” ↔ “dynamic.” We must therefore pick A and B that recreate this opposition across both halves.

Given Data / Assumptions:

• A must parallel “inert”.
• B must parallel “active”.

Concept / Approach:
Select clean antonyms describing state of motion/energy: static vs dynamic.

Step-by-Step Solution:

Verification / Alternative check:
Both pairs are widely accepted antonym pairs in standard English usage.

Why Other Options Are Wrong:

• Statics/Gymnast — mismatched parts of speech and categories.
• Helium/Participation — specific element and abstract noun, not antonyms.
• Air/Smart — unrelated domains.

Final Answer:
A. Static, B. Dynamic