Utilize the input text as a context reference, choose the right relationship between Apple Inc and iPhone from the options. Options: 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.

BENGALURU/SAN FRANCISCO (Reuters) - Apple Inc (AAPL.O) shares slumped nearly 7 percent in after-hours trading as its fourth-quarter revenue forecast fell short of estimates and it missed some targets for iPhone sales.

Answer: product_or_material_produced