Identify the odd pair: In each pair X–Y, the intended pattern is Y = X + 3. Choose the pair that does not follow this +3 rule.

Introduction / Context:
Many classification questions rely on detecting a simple arithmetic relation. Here, each option is a pair X–Y, and the rule to test is Y = X + 3. We must find the pair that breaks this rule.

Given Data / Assumptions:

• Options: 8–11, 1–4, 7–10, 3–5.
• Rule under test: Add 3 to the first term to get the second.

Concept / Approach:
Compute X + 3 for each X and compare to its Y. The odd pair will be the one where Y ≠ X + 3.

Step-by-Step Solution:

Verification / Alternative check:
Compute the difference Y − X for each pair: 3, 3, 3, and 2 respectively. Only 3–5 has a difference of 2, confirming it as the odd pair.

Why Other Options Are Wrong:

Common Pitfalls:
Rushing differences and miscomputing 3 + 3 as 5. To avoid this, always verify by subtraction as well (Y − X should equal 3).

Final Answer:
3 - 5 is the odd pair.