Cross-departmental Committees are the form of

The correct answer is D) Lateral Communication. Cross-departmental committees bring together officials from different departments who sit at roughly the same level, so the information moves sideways across the organisation rather than up or down the chain of command.

The other options are wrong for these reasons:

• Upward communication flows from subordinates to superiors, through reports, returns and suggestions.
• Downward communication flows from superiors to subordinates, through orders, circulars and policy directions.
• Optimum communication is not a recognised category of organisational communication. It is a distractor.

The core concept is Fayol's 'gangplank', a bridge that lets peers in different departments coordinate directly instead of routing every file through the scalar chain. Liaison officers, task forces and inter-departmental committees are the practical forms of this. For Mains GS-II and Ethics, this links to inter-departmental coordination failures (the 'silo' problem) in district administration.

Trap: candidates pick Upward or Downward because a committee sounds like it reports to higher authority. The question asks about the horizontal flow between peers, which is lateral.