What is the relationship between Bharti Airtel and Vodafone in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

Upholding complaints against Bharti Airtel Ltd (Airtel) and Vodafone Essar Ltd (Vodafone), ASCI said the claimed advertisements were not adequately substantiated.

Answer: owned_by