Odd one out among a @ b = c statements that share one rule

This type of question, asked 3 times: 15 Sep 2025 S2, 16 Sep 2025 S3, 17 Sep 2025 S2. All 3 questions below, oldest first.

Try each one first, then open its answer.

Question 1
15 Sep 2025 S2
9 $Find the odd one out:$
Tap an option to check your answer.
Question 2
16 Sep 2025 S3
7 $Find the odd one out:$
Tap an option to check your answer.
Question 3
17 Sep 2025 S2
8 $Find the odd one out:$
Tap an option to check your answer.