Final answer:
When driving behind another vehicle under good conditions, allow at least one second of following time for each 10 feet of your vehicle's length, making the answer C) 10.
Step-by-step explanation:
Under good driving conditions, it is recommended to allow at least one second of following time for each 10 feet of your vehicle’s length (C) when driving behind another vehicle. This means the answer to the question is C) 10. The distance you maintain from the vehicle ahead is crucial for safety to ensure you have enough time to react and stop if necessary. This rule of thumb helps to account for reaction time and stopping distance under normal driving conditions.
For example, if you are driving a 30-foot vehicle, you would want to maintain at least a 3-second following distance from the vehicle ahead of you. To estimate this distance while driving, you can use a fixed point such as a road sign or lamp post. When the rear end of the vehicle in front of you passes that point, start counting seconds ('one thousand one, one thousand two, one thousand three'). If you reach the same fixed point before you finish counting for the length of your vehicle, you are following too closely.