Final answer:
The correct documentation for a Snellen chart result of 20/60 is that the boy can see at 20 feet what others can see at 60 feet.
Step-by-step explanation:
When a 10 year old boy comes to the clinic for his well-visit and is tested with a Snellen chart, a result showing 20/60 vision indicates that what the boy can see at 20 feet, someone with normal acuity can see at 60 feet. Hence, using Snellen chart results, the correct way for the Nurse Practitioner (NP) to document the boy's visual acuity would be: "The boy can see at 20 feet what others can see at 60 feet."