Final answer:
Even though she'd read her supervisor's memo four or five times, she still found his rambling message ambiguous.
Step-by-step explanation:
The correct answer is d. Unclear. In the given sentence, the narrator is stating that even after reading her supervisor's memo multiple times, she still found his message to be ambiguous or unclear. This is indicated by the use of the word 'rambling' which suggests that the message was poorly structured or disorganized. The other answer choices, such as 'profound', 'inspiring', or 'ridiculous', do not accurately describe the supervisor's message as portrayed in the sentence.