A patient has just been intubated, and the CO₂ detector placed on the proximal end of the ETT reads 1.5%. The RT should suspect which of the following?
A. The tube is in the trachea
B. The tube is in the right mainstem bronchus and should be withdrawn 4 cm
C. The tube is in the esophagus
D. The tube is at the level of the carina and should be withdrawn 2 cm