Compare the Archaic Greek kouros with ancient Egyptian sculpture and with later, Golden Age Greek sculpture

Please provide the best answer for the statement.

1. The celebration of the male body in the Archaic Greek kouros was uniquely Greek. Egyptian sculpture did not depict the nude male form, but it obviously influenced the Greek kouros. (As early as 650 BCE, the Greeks were in Egypt.) The Greek sculpture serves the same funerary function as its Egyptian ancestors; the arms of the New York Kouros (c. 600 BCE) drop stiffly to his side and his fists are clenched in the Egyptian manner. His left foot strides forward, though both heels remain unnaturally cemented to the ground, like the Old Kingdom Egyptian statue of Menkaure with his queen.
2. During the course of the sixth century, kouroi became distinguished by naturalism. The musculature of the Anavysos Kouros (c. 525 BCE), the collarbone and tendons in the neck, and the precisely rendered feet and toes all suggest that this is a representation of a real person. In fact, an inscription on the base of the sculpture makes clear that this is a monument to a fallen hero, killed in the prime of youth.
3. We do not know why sculptors began to sculpt more naturalistically, but the reason might be related to agonizesthai, the Greek spirit of competition. Sculptors must have competed against one another in their attempts to realize the human form.
4. Remarkably, since it follows the Anavysos Kouros by only 75 years, the Doryphoros (Spear Bearer) is significantly more naturalistic. This advance, characteristic of Golden Age Athens, represents a heightened cultural sensitivity to the worth of the individual.