Final answer:
When a person's BAC reaches a level of 0.05%, the chances of having an accident increase.
Step-by-step explanation:
The question is asking about the chances of having an accident when a person's BAC (Blood Alcohol Concentration) reaches a level of 0.05%.
According to the information provided, it states that higher levels of BAC cause acute intoxication and can impair judgment and coordination. Therefore, the correct answer to the question is a. 6x.