The number of pandas is getting _____ because their living areas are becoming farm lands.[ ]

A. bigger and bigger

B. smaller and smaller

C. more and more

D. less and less

男，22岁，蓄电池厂蓄电池装配工，工作3个月后，突感脐周围绞痛，持续性疼痛，阵发性加剧。查体：神清，面色萎黄，心、肺未发现异常，腹平坦、软，无明显压疼点。血常规：RBC3.2×10/L，Hb103g/L。最可能的诊断是()

A．急性胃肠炎

B．肠结核

C．急性阑尾炎

D．铅中毒

E．消化道出血