Highlighting SummaryYou will hear a recording. Choose the paragraph that best relates to the recording.___
A. Dolphins, whales and porpoises are all social animals, but some species are more sociable than others. This depends on the environment because a species adopts the lifestyle most suitable for this. Among dolphins, forming groups makes it easier for them to find food, reproduce and gain knowledge. They are safer, too, because dolphins can communicate danger when there are threats around.
B. The speaker explains that whales, dolphins, and porpoises have evolved differently and face different threats. River dolphin numbers are declining, while ocean dolphins are doing well in spite of the threats they face. The reason for this is that ocean dolphins are better adapted for finding food and avoiding predators.
C. Dolphins have adopted group living as a response to living in close contact with other animals in the ocean, some of which kill dolphins for food. Living in social groups makes it easier to hunt for food and, in a dangerous environment, it makes sense in terms of safety to move about in large numbers.
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A. The woman's grade in biology.
B. The woman's major field of study.
C. The woman's workload.
D. The woman's lab reports.
___
A. She does not understand the biology class.
B. She does not have time to complete the assignments.
C. She does not like the class because of the lab.
D. She is not majoring in biology for premed.
___
A. It is not her favorite class.
B. Her grades in the class are low.
C. She would not mind taking it again.
D. She does not like the professor.
___
A. She wants to take an exam instead of attending the class.
B. She would like to withdraw from the professor's biology class.
C. She needs an excused absence from the laboratory sessions.
D. She has to notify her advisor that she is failing the class.
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