In order to help the student expand his/her knowledge I will help answer the question. This in hope that the student will get a piece of knowledge that will help him through his homework or future tests.
Using context clues in the paragraph 4: “A couple of decrepit apple-trees grew on the edge of it, and dropped their scanty and gnarled fruit to feast the squirrels.” The word decrepit means weak.
so the answer is letter C) weak
I hope it helps, Regards.