In the past, the transition to young adulthood occurred when people were married, entered parenthood and started stable work. Around what age does this happen for most people today who live in developed countries?

18 years old

Explanation:

The passage to adulthood in developed countries ranges from 18 to 21 years, although in some countries, such as the US, people below this age are judged as adults when committing serious crimes in some states.

In the US, adulthood is gradually released to young people. Thus, with each age, some freedom is given to the young person who learns to create a sense of responsibility and is given the duties of adult citizen by parties.

However, the scientific consensus suggests that 18 years is the transition age from adolescence to adulthood in which the young person acquires greater discernment, maturity and responsibility. This is the age practiced in most developed countries.