1. Multiple Choice (單選題）（25 pts) (1) If k is the least numbers of integers must be selected from {1，3, 5,…，29} to make sure there is at least o： pair of these integers with the sum 26, then k is (A) 6-8 (B)9〜11 (C) 12〜14 (D) 14〜16 (E) none of above.