Answer:
"Park staff are monitoring invasive species such as the emerald ash borer."
Explanation:
C, the answer is is c because the frost comes before the snows first fall
Answer: Enthralled means to be suprised, or having a lot of enjoyment that you forget about your surroundings. Also, something caught her/his attention that they forgot about anything else is another good example.
Try to use this context to pick out the best phrase for your question. Have a good day!