That is incorrect. The correct punctuation would be:
Crossing a highway may be fatal for skunks, opossums, and squirrels.
Gloat in the sentence means to brag. Basically, the third selection. "To make fun of someone."
Hopefully this helps :)
School starts in a week so Aubrey and her grandmother go "back to school" shopping. Aubrey is not excited for school because she will not know anybody other than Bridget. Her and Bridget spend the last few days of summer playing outside. The first day of school is actually on Aubrey's little sister's birthday which makes it even worst. After the day is over Aubrey actually likes her new school.
Hope that helps
The correct answer is The alligator slipped quietly into the water.
The first sentence does not agree since alligators should be a singular form, while the second and third are nonsensical because of lack of information.