The correct answer is C. Continuous work
Step-by-step explanation:
The word "toil" which is the word in italics or bolded word is used to describe works that are exhausting, continuous or that require a great effort to be complete. This implies, in the case of the sentence presented, the writer uses the word "toil" to emphasize the effort and time it took to the teenagers to complete the fort in the neighborhood. According to this, the phrase that best matches this word is "continuous work" because this is the only one that fits the meaning of "toil" as hard or endless work. Also, "haphazard work" is not correct as this describes a type of work that is unplanned.