What is the relationship between Mobily and Saudi Arabia 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.

DUBAI, Aug 3 (Reuters) - Major Gulf stock markets edged up on Monday after Sunday's sell-off but Saudi Arabia lagged because telecommunications operator Mobily tumbled following yet another negative earnings restatement.

Answer: headquarters_location