the answer would most logically be D. Plus, it said " completely soiled" which is also an indication that the definition of the bold word is dirt. Also, soil is a noun (and once again can be used in turn for dirt) which further helps to get the answer D. Finally, the noun in which is used is at the end, and the sentence structure and the place where the noun is, would also make "D" the correct answer. (Hope it helps)
