Answer:
a pet parrot talking
Explanation:
dogs responding to "roll over"
Providing long-term control over the body's internal conditions
Keeping conditions within a normal range
Adjusting the "set point" for body temperature based upon level of activity
I would say A. Because it seems like a logical explanation.
There's been a lot of bad news for polar bears recently. In 2007, for example, scientists reported that if global warming continues unabated, the population could drop two-thirds by 2050.