Where must the environmental sticker be placed on a vehicle according to DGT guidelines?

A)On the lower left corner of the front windshield, or anywhere on the rear window.
B)On the lower right corner of the front windshield, or in any visible location if the vehicle has no windshield (such as a motorcycle).Correct
C)It can be kept in the glove compartment as long as it is physically present inside the vehicle.

The DGT specifies that if the vehicle has a windshield, the sticker must be placed in the lower right corner. For motorcycles or vehicles without a windshield, it simply needs to be affixed to a clearly visible spot.