阅读理解。阅读下列四篇短文，从每小题后所给的A,B,C或D四个选项中，选出最佳选项。
Driving a car is not just handling controls and judging speed and distance.It requires you to predict what other road users will do and get ready to react to something unexpected.When alcohol is consumed，it enters your bloodstream and acts as a depresant (抑制药)，damaging eyesight，judgement and c oordination (协调)，slowing down reaction time and greatly increasing the risk of accidents.Even below the drink driving limit，driving will be affected.
Alcoho l may take a few minutes to be absorbed into the bloodstream and start action on the brain.Absorption rate is increased when drinking on an empty stomach or when consuming drinks mixed with fruit juice.To get rid of alcohol from the body is a very slow process and it is not possible to speed it up with any measures like taking a shower or having a cup of tea or coffee.
The present Road Traffic Ordinance states clearly that the limit of alcohol concentration is：
