What is the relationship between 'Caltex' and 'Oil' in the context of the input sentence.
Options: employer, product/material produced, owner of, position held

Trading ex dividend today: APN Outdoor, Adacel Technologies, Blackmores, Caltex Australia, Canterbury Surrey Hills, Cardno, MMA Offshore, Oil Search, Phileo Australia, Ramsay Health Care, Saunders International, Service Stream, SpeedCast International.
product/material produced