D) How serious their protein deficiency is and what remedies they use.

D）他们蛋白质缺乏的严重程度以及他们采用的补救措施。

Mothers and nurses tell us that they cure these things by I know not what remedies.

母亲和护士告诉我们， 他们用我不知道什么疗法来治愈这些疾病。