Please answer asap! :)

Read the sentence below and answer the question that follows.
A 47-year study by scientists in Great Britain revealed that the Parus major is laying eggs approximately two weeks
earlier
Which led the Parus major to change its behavior?
A) It is making the most of the availability of seasonal food.
B) It is using leaves and other vegetation that is now sprouting earlier.
C) It is arriving from migration earlier due to warmer weather.
D) Its individual adaptability from year to year has been studied.
E) Its nests need the camouflage offered by trees with leaves.