The nurse is talking with the nursing student about the size of a child's trachea. The nurse gives an illustration for the student to understand more clearly. Which statement is correct regarding the size of a child's trachea?

a. "The size of the child's trachea is the same size as an adult."
b. "The size of the child's trachea is the size of the child's thumb."
c. "The size of the child's trachea is the size of the child's little finger."
d. "The size of the child's trachea is the size of the child's index and middle finger combined."