They're probably looking for false, but to be honest, I use it in my writing sometimes. It depends on the setting and character, or it should be specified as slang in nonfiction writing.
First one is C! Because it explains what’s wrong with the lack of fast food in not populated areas. Second one is B! Because they cannot afford much therefore it’ll have a bad outcome. The last one I was a little confused on but It’s likely A.
