You are caring for an 8-month-old infant with a tracheostomy. Upon assessment, you visualize secretions within the tracheostomy that require suctioning. In preparation to suction the infant's tracheostomy, which of the following setting would be the most appropriate suction setting?
A. 120 mmHg
B. 90 mmHg
C. 60 mmHg
D. 40 mmHg