Which pronoun in the passage does not agree in number with its antecedent?
Becoming a Nurse

If a person wants to become a nurse he or she must first complete high school. After high school, students have two options; they can get a two-year Associate's Degree in Nursing (ADN) or a four-year Bachelor's of Science Degree in Nursing (BSN). If a nurse gets a BSN, they are considered professional-level. Many nurses choose to first get an ADN and then use their employer's tuition-program to pay for more advanced training.