What distinguishes stage 4 of the Tanner scale in males?

• A. Development of adult genitalia
• B. Increased size of penis and glans
• C. Complete absence of pubic hair
• D. Growth of breast tissue

Answer: (B)

Stage 4 of the Tanner scale in males is characterized by the increased size of the penis and glans. During this stage, individuals experience significant physical development, including an elongation of the penis and further enlargement of the glans, which are key indicators of maturation in male genitalia.

Tanner stages are used to assess physical development during puberty, and stage 4 represents a transitional phase where changes are becoming more pronounced compared to earlier stages. In stage 4, boys will also typically exhibit further increases in testicular size and development of scrotal skin texture, but the most defining feature is indeed the notable increase in the size of the penis and glans.

The other aspects mentioned in the choices do not accurately reflect stage 4. Development of adult genitalia might be partially true as it's a general descriptor for later stages, but it does not specifically pinpoint what stage 4 entails. Complete absence of pubic hair would be more characteristic of earlier Tanner stages, and the growth of breast tissue is not a feature associated with males in this classification.