Logical Reasoning STEM Practice Test

All A are B; No B are C. What is necessarily true about A and C?

A and C share some members No A are C All A are C Some C are A

Correct Answer:

No A are C

Explanation:

Understanding how set relationships translate to what must be true is key here. “All A are B” means A is entirely inside B (A ∨ B). “No B are C” means B has no elements in common with C (B ∨ C = ∨). Since A is a subset of B and B has no elements in C, A cannot have any elements in C either. Put another way, there’s no overlap between A and C. So the only necessarily true statement is that no A are C. Because A lies within B and B doesn’t touch C, any claim that some A are C, or that all A are C, or that A and C share elements, would contradict the given conditions.

Access more questions from this quiz

Continue to Logical Reasoning STEM Practice Test for more practice questions and the full quiz experience.

Access More Questions