Select the meaning of the capital word in this sentence: Fearful that the fever might have an ADVERSE effect, Catriona called the doctor for an emergency appointment.

The word "ADVERSE" in this context refers to something that is harmful, unfavorable, or negative. Catriona's concern about the fever suggests that she is worried about potential negative consequences for her health. The choice "C. Negative" captures this meaning accurately, emphasizing that an adverse effect would be an unwanted or detrimental outcome. The other options convey meanings that do not align with the idea of being harmful or detrimental; instead, they may imply something positive, beneficial, or carefree, which does not fit the context of Catriona’s urgent call to the doctor.