Which of the following statements about an airport is true?

The statement that defines an airport as an aerodrome with an airport certificate in force is accurate because it highlights the regulatory framework that establishes the operational parameters of an airport. An aerodrome refers to a defined area on land or water that is used for the arrival, departure, and maintenance of aircraft, regardless of whether it has formal certification. However, to be classified specifically as an airport, this space must possess an airport certificate, which indicates compliance with safety and operational standards set by aviation authorities. This certification often involves regular inspections and adherence to specific regulations, ensuring that the facility is adequately equipped to handle the complexities of air travel, such as passenger processing and air traffic control.

The other statements fail to capture the essential regulatory aspect defining an airport. For example, not all airports are required to have multiple passenger terminals or a control tower, as smaller regional airports may not have such facilities. Additionally, while certified airports are preferable for international operations, it is possible for some unlicensed airports to still facilitate international flights under specific conditions, emphasizing that certification is a key aspect but not the sole requirement for such operations.