Visitors at Algonquin Park in Northern Ontario May Miss Out

Visitors at Algonquin Park in Northern Ontario may miss out on the brilliant red colouration of Acer sacchrum in autumn because

A) the timing is genetically programmed and the people didn't come at the right time.
B) these animals have already gone into hibernation by then.
C) these trees don't produce anthocyanin so far north.
D) anthocyanin production and chlorophyll loss are responses to environmental cues and it may have happened already.
E) Acer sacchrum doesn't live in the park.