[单选题]The paragraph is followed by an incomplete phrase or sentence which summarizes the main idea of the paragraph. Choose the missing words of the phrase or sentence.


Beijing's army recruitment efforts have been increasingly hampered in recent years by a decline in the physical fitness of candidates, with many being ruled unsuitable due to common complaints such as being overweight or shortsighted. Around 60 percent of college students who apply for military service cannot pass the physical fitness exam.

Students' （） to meet army fitness standards.