would a green apple be considered a citrus fruit?!
No. Citrus fruits contain significant amounts of citric acid. Common examples include oranges, lemons, limes, grapefruit, tangerines.
No... citrus fruits are a special category that include oranges, lemons, limes, grapefruit, and kumquats. They all are similar in that you can break their flesh apart in sections with out the use of a knife. Apples are not like that -- you'd need a knife to cut apart an apple!
Nope... but the flavor can resemble a citrus fruit. Citrust fruits are