Utilize the input text as a context reference, choose the right relationship between 'Starbucks' and 'coffee' from the options.
Options: distributed by, chairperson, product/material produced, publisher

Starbucks (Swiss: SBUX.SW - news ) , the world's biggest coffee chain, said on Tuesday it had no plans to enter Iran, while Coca-Cola said it was too early to comment.
product/material produced