Which records or documents shall the owner or operator of an aircraft keep to show compliance with an applicable air-worthiness directive?
a. aircraft maintenance records.
b. air-worthiness certificate and pilot's operating hand-book.
c. air-worthiness and registration certificates.

Explanation:

Air Worthiness is the measure of whether an aircraft is suitable for the safe flight or not. The national aviation authority gives the certificate of airworthiness, it is maintained by the national aviation authority to perform the required maintenance actions. Airworthiness certificate are valid as long as the aircraft meets the approved type design and is in a condition for safe maintenance and operation, alterations and preventative maintenance as per 14 CFR, parts 21, 43 and 31.

Airworthiness certificate, registration certificate, weight and balance information and operating limitations are the documents required for an aircraft's airworthiness.

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