What is the purpose of field sobriety tests?

Answer: B — To evaluate a driver's physical and cognitive abilities

Field sobriety tests are designed to evaluate a driver's physical and cognitive abilities, allowing law enforcement to assess whether a person is impaired by alcohol or drugs while driving. These tests often include tasks that measure balance, coordination, and the ability to follow directions, which are critical skills necessary for safe driving. A driver's performance on these tasks can indicate impairment, even though the tests do not measure blood alcohol concentration (BAC) directly. While measuring BAC is crucial for determining legal intoxication levels, field sobriety tests serve as an initial assessment tool. They help officers make informed decisions about whether further testing, such as breath or blood tests, is necessary. Other options—like distracting the driver or measuring speed—do not accurately reflect the purpose of these tests, while the precise measurement of BAC is typically conducted through chemical tests rather than physical assessments.