Answer: C. she explains the specific stresses each of the helpers faces.
Step-by-step explanation: In the given passage we can see the description of three different situations, the first one is Elli's, she has diphtheria which prevents her to be in contact with other people for six weeks (because of the contagious disease), the second one is the one of Koop house, which is sick and only has had only porridge and milk for three weeks, and the third situation is from Kraler who is really busy. By explaining the specific stresses each helper faces, the author creates the worried mood.