Hello!
The answer is C. Hibernate during the cold winter months.
Why?
Alpine marmots are known for having a long hibernation duration which starts in October (winther) and ends in April (summer) (about 7 months). During this long period, they are able to reduce their bear beats from 200 per minute to just 30 or 38 beats, and their breaths from 60 breaths/minute to 1-3 breaths/minute, guaranteeing an extreme energy saving process.
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