Take context from the input text and decide on the accurate relationship between 'Volvo' and 'Truck' from the options provided.
Options: product/material produced, founded by, owner of, brand

In what was then the largest environmental enforcement case in U.S. history, companies including industry leaders Caterpillar Inc., Cummins Engine Co., Mack Trucks and Volvo Truck Corp. agreed to pay $83.4 million in fines and reprogram the computers.
product/material produced