Classify the relation of question with context to one of these categories: 1) award received, 2) based on, collection, 3) conflict, 4) constellation, 5) convicted of, 6) date of death, 7) director, 8) drafted by, 9) educated at, 10) medical condition, 11) military branch, 12) narrative location, 13) occupation, 14) original network, 15) parent company, 16) point in time, 17) production company, 18) residence, 19) series, 20) service entry, 21) sex or gender, 22) spouse, 23) standards body question.
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Question: Context : Domitia Longina (c. AD 53-55--c. AD 126-130) was an Empress of Rome and wife to the Roman Emperor Domitian. 
Question : What is Domitia Longina's spouse's name?

Answer: spouse


Question: Context : The AK-63 (also known in Hungarian military service as the AMM) is a Hungarian variant of the AKM assault rifle manufactured by the Fegyver- és Gépgyár (FÉG) state arms plant in Hungary. 
Question : What year did AK-63 come into use?

Answer: service entry


Question: Context : ISO 3166-2:HK is the entry for Hong Kong in ISO 3166-2, part of the ISO 3166 standard published by the International Organization for Standardization (ISO), which defines codes for the names of the principal subdivisions (e.g., provinces or states) of all countries coded in ISO 3166-1. 
Question : Who set the standards for ISO 3166-2:HK?

Answer:
standards body