Final answer:
The minimum age to hold a commercial driver's license (CDL) varies by state. Most states require individuals to be at least 18 years old for intrastate driving and 21 for interstate driving.
Step-by-step explanation:
The minimum age to hold a commercial driver's license (CDL) in the United States varies depending on the state. However, most states require individuals to be at least 18 years old to obtain a CDL for intrastate driving, which means driving within the state's borders. For interstate driving, which involves driving across state lines, the minimum age is usually 21. Additionally, individuals must pass written and practical tests to demonstrate their knowledge and skills related to commercial driving.