Final answer:
The statement is False. Cutting an intubation tube to a specific length can be dangerous for the patient.
Step-by-step explanation:
The statement is False. A 7.5 mm intubation tube should not be cut to a length of 21 cm. The length of an intubation tube depends on the patient's size and specific medical needs. It is calculated based on measurements such as the distance from the patient's lips or teeth to the carina (where the trachea divides into the bronchi). Therefore, cutting an intubation tube to a specific length without considering these factors can be dangerous for the patient.