Set 1: Words in Context
Explanation
PASSAGE
Dr. Aristham's research suggests that REM sleep is ______ for cognitive function, as it is during this phase that the brain consolidates memories from the day.
Which choice completes the text with the most logical and precise word or phrase?
Detailed Explanation
The text states that the brain consolidates memories during REM sleep, implying it is a necessary process for cognitive function. 'Essential' means absolutely necessary.
Key Evidence:
• "consolidates memories"
• "cognitive function"
Why others are wrong: A (Irrelevant suggests it doesn't matter, but memory consolidation is important.), B (Optional suggests it's not needed, but the context implies a key function.), D (Detrimental means harmful, which contradicts the positive function of memory consolidation.).