Refer to the input text as context and select the correct relationship between 'BMW Z4' and 'BMW' from the available options.
Options: original broadcaster, brand, location of formation, parent organization

In January this year, Transstroy signed three car loan agreements for Rs 4.73 crore with Alphera Financial Services, a financing arm of BMW Group Financial Services, to buy a Lamborghini Huracan coupe, a Mercedes Benz S350 and a BMW Z4 sDrive.
brand