Congruence

Some of the more difficult test questions I recall from graduate school examinations had to do with bipartite statements.

What one was asked to ascertain, as the test taker, was whether parts A and B were both true and related, true but unrelated, or if either part were false, or both were.

So options for answers would be:

A — both parts true and related

B — both parts true but unrelated

C — only part A was true

D — only part B was true