Which of the following figures accurately depicts the inter-conversion of the three states of matter?

The correct option is b.

Explanation:
Matter exists in three primary states: Solid, Liquid, and Gas. These states can inter-convert from one form to another by changing temperature or pressure. The correct processes for these conversions are as follows:

1. Solid to Liquid: The conversion of a solid into a liquid is called Fusion (or melting).
2. Liquid to Solid: The conversion of a liquid into a solid is called Solidification (or freezing).
3. Liquid to Gas: The conversion of a liquid into a gas is called Vaporisation.
4. Gas to Liquid: The conversion of a gas into a liquid is called Condensation.
5. Solid to Gas: The direct conversion of a solid into a gas without passing through the liquid state is called Sublimation.
6. Gas to Solid: The direct conversion of a gas into a solid is called Deposition.

Analysis of the given figures:
- Figure (b): Accurately shows all arrows with their correct labels:
• Solid → Liquid: Fusion
• Liquid → Solid: Solidification
• Liquid → Gas: Vaporisation
• Gas → Liquid: Condensation
• Solid → Gas: Sublimation
• Gas → Solid: Deposition
- Figure (a): Incorrectly labels the Solid → Liquid process as "Vaporisation" and Gas → Liquid as "Fusion".
- Figure (c): Incorrectly labels Liquid → Solid as "Deposition".
- Figure (d): Incorrectly labels Liquid → Solid as "Condensation" and Gas → Liquid as "Deposition".

Hence, Figure (b) is the only figure that correctly depicts the inter-conversion of all three states of matter.