Final answer:
The safest portion of the lane to ride in when a large vehicle is approaching is the right portion, as it increases visibility and safety.
Step-by-step explanation:
When a large vehicle is approaching, the safest portion of the lane to ride in is the right portion. This position increases visibility for both the cyclist and the driver of the approaching vehicle and provides the most space between the two. It is important to always follow traffic rules and regulations and to be aware of your surroundings for the safety of all road users.