Comparison group is cluster of people in form of group that is used for evaluating and comparing task performed so that working condition of experiment can be known. Comparison group is subjected with same condition and equipment to measure progress and impact of experiment.
According to the question, Hilda does not have comparison group with whom she can actually compare that natural disasters effect on people as stress and distress.She cannot evaluate the condition of people without any similar reference.
Utilitarianism theory is a theory that focuses on the outcome of an event to determine right from wrong according to the action or policy being put in place. In this theory the interests of others need be taken into account.