Driving with **excessive heat** inside the vehicle can be dangerous because it **promotes the onset of fatigue** at the wheel. Fatigue can lead to distractions and errors, increasing the risk of accidents. Additionally, heat can make you need more time to react to unforeseen situations and can increase aggressiveness towards other drivers.

To avoid these risks, it is important to keep the vehicle at an appropriate temperature, between **20 and 23 degrees**, using air conditioning. It is also recommended to take more breaks during the trip and stay hydrated by drinking water or juices. Wearing light, loose-fitting, and light-colored clothing can help you feel more comfortable and reduce the impact of the heat.

Therefore, excessive heat does increase the risk in driving by promoting fatigue, which confirms that the **correct answer is option 1**.