1. Correct Answer: Colonel

2. Explanation of Options:

 • Option (a): Lieutenant Colonel  
 • Incorrect.
 • A Lieutenant Colonel in the Indian Army is equivalent to a Squadron Leader in the Indian Air Force.
 • The rank of Lieutenant Colonel is one step below the rank of Colonel.
 • Therefore, it does not match the rank of Wing Commander.

 • Option (b): Colonel  
 • Correct.
 • A Colonel in the Indian Army is equivalent to a Wing Commander in the Indian Air Force.
 • Both ranks are considered senior officer ranks and hold similar responsibilities and authority within their respective services.
 • This equivalence is part of the structured rank parity between the Indian Armed Forces.

 • Option (c): Brigadier  
 • Incorrect.
 • A Brigadier in the Indian Army is equivalent to an Air Commodore in the Indian Air Force.
 • The rank of Brigadier is one step above the rank of Colonel.
 • Therefore, it is higher than the rank of Wing Commander.