-According to the graph, what is the relationship between stress and the likelihood of infection by a cold virus?

A) People with a stress index of 3-4 are more likely to catch a cold.
B) People with a stress index of 5-6 are more likely to catch a cold.
C) People with a stress index of 11-12 are more likely to catch a cold.
D) People at all stress levels have an equal chance of catching a cold.