If the italicized word or phrase is 'green and slender' , then the correct answer is 'appositive', due to the fact that appositives are always placed between commas and separated from the rest of the sentence, and they modify, describe or refer to the noun they rename which is right besides it. The appositive can be a short or long combination of words. it provides information that further identifies or defines the noun they modify. Option B is correct.
