Classification (leader vs member): Three pairs denote a leader of a collective; one pair denotes a member of a collective. Identify the odd pair.

Introduction / Context:
Role–collective relations can be of two types: leadership (head of a body) and membership (part of a body). Three options encode leaders; one simply encodes a member. The aim is to spot the membership relation amid leadership relations.

Given Data / Assumptions:

• Captain → Team (leader).
• Boss → Gang (leader).
• Prime Minister → Cabinet (heads/co-ordinates cabinet).
• Artist → Troupe (member performer, not inherently the leader).

Concept / Approach:
Check whether the left term is the titular head of the right-hand collective. If the left term is simply one of many members, that pair is the odd one out.

Step-by-Step Solution:

Verification / Alternative check:
Substitute a leadership title. “Director : Troupe” would align with the others; “Artist : Troupe” does not.

Why Other Options Are Wrong:

Common Pitfalls:
Assuming a skilled member equals leader. Titles identify leadership explicitly.

Final Answer:
Artist : Troupe