Final answer:
In California, authorities can arrest an underage driver for DUI with a BAC of 0.01%. This low tolerance reflects the strict standards imposed by the National Minimum Drinking Age Act of 1984.
Step-by-step explanation:
For an underage driver in California, a blood alcohol concentration (BAC) of 0.01% gives authorities the legal right to arrest the individual for DUI. The National Minimum Drinking Age Act of 1984 required states to raise their drinking age to twenty-one or face a reduction in federal highway funds. It is important to note that the effects of alcohol vary between individuals and the only effective way to avoid alcohol toxicity is to give the liver enough time to metabolize the ingested alcohol.