Stalactites, hanging formations on the roof if a cave, are formed when water rich in calcium carbonate drips through the cracks in the rock above. Which statement about the sentence is true? A) the appositive phrase changes the essential material. B) the appositive phrase contains non essential material. C) the appositive phrase modifies the word formed. D) the sentence does not contain an appositive phrase

The correct option is B.

An appositive phrase refers to a noun or a pronoun that identifies or rename another noun or pronoun; it gives more information about that noun or pronoun. An appositive together with its modifier is called an appositive phrase. An appositive phrase is said to be non - essential when it adds information to a sentence whose meaning is already clear. Non-essential appositives are usually set off by a coma.

B. the appositive phrase contains nonessential material.