- Step 1: Constraints: A and B not together, C and D not together.
- Step 2: Valid teams: (A, C), (B, D) and (A, D), (B, C).
- Step 3: Other combinations (e.g., (A, B), (C, D)) violate constraints.
- Step 4: Count: Two valid arrangements.
- Step 5: Check options: Option (2) is 2, which matches.
- Step 6: Verify no other valid pairings.