I don't really understand what u r asking but centeral idea is main idea if that's what u r asking...
About discovering is a gerund phrase
The first one is C, George Washington.
The second question is D, New Colossus.
The third one is A The Star-spangled Banner.
Since bees help pollinate plants, a lack of pollination could prevent certain species of vegetation from growing. Therefore, the plants could be driven into extinction. These plants act as a food source to many animals, so if the animals have nothing to eat, they'd die off as well. Consequently, our own food supply of crop and animal would decrease.
