Which hormone is primarily associated with the development of male physical characteristics?

Testosterone is the primary hormone associated with the development of male physical characteristics. This steroid hormone is produced mainly in the testes and is crucial for the growth and development of male reproductive tissues, such as the testes and prostate, as well as promoting secondary sexual characteristics like increased muscle and bone mass, body hair growth, and deepening of the voice during puberty.

In addition to these physical developments, testosterone plays a key role in the regulation of various bodily functions, including libido and mood. Its influence extends beyond just physical characteristics; it affects energy levels and overall well-being in men. This hormone's significant role in masculinization during embryonic development means that its presence is essential for defining male traits and features throughout a man's life.

In contrast, other hormones listed, such as estrogen and progesterone, are primarily associated with female characteristics and reproductive functions. Cortisol, known as the stress hormone, has various roles in metabolism and the body's response to stress but is not directly related to the sexual differentiation seen with testosterone.