Final answer:
In a staggered formation of riders passing a car, the lead rider should return to the left portion of the lane for increased visibility and defensive positioning.
Step-by-step explanation:
When riders in a staggered formation are passing a car, after the lead rider passes, he/she should return to the left portion of the lane. This position in lane formation is often recommended for motorcycle riders as it increases visibility and helps to prevent the rider from being in the blind spot of a car. It's also a strategic position for defense driving as it allows a better view of the road ahead, giving the rider more time to react to traffic conditions.