'TO THE FRONT DOOR' is the underlined word. The correct option is B.
A prepositional phrase is a group of words which does not have either a subject or a verb and it serves as a unified part of a sentence. It is usually made up of a preposition and a noun or pronoun. There are two types of prepositional phase, adjectival and adverb prepositional phrase. The adjectival prepositional phrase modifies noun or pronoun while adverb prepositional phrase modifies verbs, adjectives or adverbs.
In the sentence given in this question, the underlined prepositional phrase modifies the verb 'dashed', thus, it is an adverbial prepositional phrase.
