In most jurisdictions, a blood-alcohol content (BAC) of 0.08 percent is commonly considered the legal limit for driving under the influence (DUI). Levels such as a BAC of 0.25 percent and 4.0 percent are generally well above this limit and would likely warrant an arrest.
However, a BAC of 0.03 percent is usually regarded as relatively low and does not typically warrant an arrest, as it is below the legal limit for driving intoxicated in many places. Hence, the correct answer would be:
BAC of 0.03 percent