A class of 12 is divided into 4 groups of 3. Sam and Tom are in different groups. Uma and Val are in the same group. If the teacher is also assigned to a group, which group has 4 members?
✓ Correct Answer: Option C
12 students + 1 teacher = 13 people in 4 groups. One group gets 4. We don't know which group the teacher joins without additional constraints.