This is an excerpt from a history of the ancient Greek state of Sparta. Read the passage carefully to determine the central idea. But as soon as [young Spartans] were seven years old, Lycurgus ordered them all to be taken by the state and enrolled in companies, where they were put under the same discipline and nurture, and so became accustomed to share one another’s sports and studies. The boy who excelled in judgement and was most courageous in fighting, was made captain of his company; on him the rest all kept their eyes, obeying his orders, and submitting to his punishments, so that their boyish training was a practice of obedience.

–“Life of Lycurgus,”
Plutarch

What is the central idea of the passage?

Young Spartans were not required to attend school.
Young Spartans were expected to read and write.
Young Spartans were not encouraged to play with other children.
Young Spartans began physical and mental training at a young age.