Answer: (B) year, depending
Step-by-step explanation:
This sentence is describing the amount of time it takes to mend a fracture, which depends on three factors: the size of the bone, the location of the fracture, and the age of the person. The phrase "from four weeks to a year" describes a range of time, and the word "depending" introduces the factors that determine the length of time. So the best way to complete the sentence is "Mending a fracture takes from four weeks to a year, depending on the size of the bone, the location, and the age of the person."