If she ___________ about his financial situation, she would have helped him out.
-
knew
-
had been knowing
-
had known
-
have known
C
Correct answer
Explanation
This is a Third Conditional sentence describing a hypothetical past situation and its result. The structure is 'If + Past Perfect, ... would have + Past Participle'. 'Had known' is the past perfect form required. 'Knew' is simple past, 'had been knowing' is incorrect because 'know' is a stative verb not used in continuous form, and 'have known' doesn't fit the conditional structure.