Read the case history and then answer the questions.
A Hike, a Tick, and a Telltale Rash
Emma Katherine, a 21-year-old college student attending school in Massachusetts, was in good health until she developed a fever, nausea, headache, and muscle pain. A few days later, she developed a rash on her forearms—small, flat, pink, non-itchy spots. She went to her physician, who asked, among other things, what she had been doing over the past month. She told him about a trip she had taken three weeks earlier to North Carolina, where she hiked through the woods for a couple of days. The expedition was incident free until one morning when she discovered an ugly tick on her back, which was removed quickly. She encountered no other people or animals during her trek. About a week later, she started exhibiting the symptoms that sent her to the doctor's office. Emma's signs, symptoms, and travel history led the doctor to suspect that Emma might have Rocky Mountain spotted fever. How could Emma have contracted this disease if she was near no people who might carry this disease?
Through which of the following methods did Emma contract the bacteria that causes Rocky Mountain spotted fever?
Choose one:
A. Insect vector
B. Vertical transmission
C. Vehicle transmission
D. Skin-to-skin contact