Some A are B. No B are C. What can be concluded about Some A are not C?

• A. Some A are C
• B. Some A are not C
• C. No A are C
• D. All A are C

Answer: (B)

The key idea is combining existential and universal negation. "Some A are B" guarantees there is at least one element that lies in both A and B. "No B are C" means B and C have no elements in common. Therefore that particular A in B cannot be in C. So there exists at least one A that is not C.

That is the definite conclusion you can draw. The other options aren’t guaranteed: there could be A elements in C that aren’t in B, so we can’t conclude No A are C or Some A are C. And All A are C would require every A to be in C, which would clash with the fact that some A are B (since B and C don’t overlap).