Final answer:
Alcohol consumption impairs judgment and reason, which is the first effect on a driver. It can lead to decreased reaction time, poor coordination, and at higher doses, acute intoxication or unconsciousness. Alcohol is a depressant and affects skills necessary for safe driving. The correct option is D.
Step-by-step explanation:
Alcohol first affects a driver by impairing judgment and reason. The consumption of alcohol leads to a range of changes in consciousness, starting with euphoria at lower doses and leading to sedation and decreased reaction time as the dose increases.
Driving under the influence is particularly dangerous because it affects tasks that require skill and judgment. For this reason, many jurisdictions define legal intoxication at a blood alcohol concentration (BAC) of 0.08%. High levels of alcohol can lead to acute intoxication, unconsciousness, and even death. Moreover, alcohol is classified as a depressant, and even at low doses, it can cause poor coordination and impaired judgment.