Answer:
The correct answer is option D) The participial phrase Crunching popcorn modifies girl.
Step-by-step explanation:
A participial phrase if formed by verb+ing + objects and modifiers. Participial phrases act as adjectives and they modify nouns.
In the example provided, the participial phrase is "crunching popcorn" and the noun it modifies is "girl".
The rest of the options are incorrect since in option A) the participial phrase is not modifying a noun but an adjective (teenage), in option B) and C) the participial phrase is incorrect.