Utilize the input text as a context reference, choose the right relationship between ConocoPhillips and Petroleum 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.

Both Marathon Petroleum and Phillips 66 were the downstream arms spun off from their parents in 2011 — Houston-based Marathon Oil Corp. (NYSE: MRO) and Houston-based ConocoPhillips (NYSE: COP).

Answer: product_or_material_produced