Question

influenza, or the flu, is an infectious disease that affects mammals and birds. the flu cannot be treated with antibiotics because
○a. it is caused by a fungus, not a bacterium.
○b. it is caused by a virus, not a bacterium.
○c. it is caused by a highly resistant strain of bacteria.
○d. it is caused by two unique strains of bacteria.

Explanation:

抗生素只能治疗由细菌引起的疾病，而流感是由病毒引起的，所以不能用抗生素治疗。

Answer:

B. it is caused by a virus, not a bacterium