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