Take context from the input text and decide on the accurate relationship between 'Tata Steel' and 'steel' from the options provided.
Options: subsidiary, chairperson, product/material produced, stock exchange

Tata Steel: Tata Steel on Wednesday said production of coke has started at its Kalinganagar project in Odisha and it is set for commissioning of the first phase of its 3 million tonne steel plant.
product/material produced