Which is the shortest distance to see a thing very clear by a human being?

The shortest distance at which a human can see an object clearly is known as the near point, typically around 25 centimeters (about 10 inches) for a young adult with normal vision. However, this distance can vary based on individual factors such as age and eye health. As people age, the near point often increases due to changes in the eye's lens, making it harder to focus on close objects.