What topics related to the Nightcap Oak does the professor mainly discuss？ Choose 2 answer

What topics related to the Nightcap Oak does the professor mainly discuss？ Choose 2 answers.

A．Factors that relate to the size of the area in which it grows

B．The size of its population over the last few centuries

C．Whether anything can be done to ensure its survival

D．Why it did not change much over the last one hundred million years

此题为多项选择题。请帮忙给出正确答案和分析，谢谢！