【名词&注释】
病原菌(pathogen)、菌群失调(dysbacteriosis)、可逆性(reversibility)、不一致(inconsistency)、病原学诊断(etiological diagnosis)、呼吸道感染病原学(pathogens in respiratory infection)、下呼吸道分泌物(lower respiration secretion)
[单选题]下呼吸道感染病原学(pathogens in respiratory infection)诊断中,人工气道吸引采集的下呼吸道分泌物(lower respiration secretion)病原菌数为()
A. ≥102cfu/ml
B. ≥103cfu/ml
C. ≥104cfu/ml
D. ≥105cfu/ml
E. ≥106cfu/ml