What is the relationship between Apple Inc and Nasdaq 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.

However, after initially rising and helping to lift the Nasdaq in the wake of an Oppenheimer & Co upgrade, shares of Apple Inc ( AAPL.O ) retreated as its performance at the Macworld expo in San Francisco disappointed investors.

Answer: stock_exchange