At an intersection, when should large vehicles activate their blinker?

For large vehicles, activating the blinker 100 feet prior to an intersection is crucial for safety and communication with other road users. This distance provides ample warning to nearby drivers, allowing them time to adjust their driving behavior in response to the larger vehicle's intended maneuver. Given the size and slower turning capabilities of large vehicles, signaling well in advance helps prevent accidents and ensures smoother traffic flow.

While the other options offer varying distances, they do not align with the commonly accepted practices for large vehicles in Texas. Activating the blinker too close to the intersection may not give other drivers enough time to react appropriately. Thus, 100 feet is the appropriate distance to ensure visibility and safety for both the large vehicle and other road users.