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Answer: BSet 3: Inferences
Explanation
PASSAGE
Octopuses have three hearts. Two hearts pump blood to the gills, while the third pumps it to the rest of the body. Interestingly, the heart that delivers blood to the body stops beating when the octopus swims, which is why these animals prefer crawling—swimming exhausts them quickly.
What can be inferred about octopus locomotion?
A. Swimming is their most efficient form of movement.
B. Their cardiovascular system makes sustained swimming energetically costly.✓ Correct
C. They have only one functional heart.
D. They avoid crawling whenever possible.
Detailed Explanation
When swimming, one heart stops—reducing blood flow. This makes swimming exhausting, implying crawling is more sustainable.
Key Evidence:
• "heart stops beating when the octopus swims"
• "swimming exhausts them quickly"
Why others are wrong: A (Swimming is exhausting, not efficient.), C (They have three hearts; one just pauses.), D (They 'prefer crawling.').