The first visible signs of senescence may be observed in the

_____________________ focuses on the complex set of systems and interacting social layers that can affect children's development

A) Psychoanalytic theory B) Ecological systems theory C) Information processing approach D) Biological theory

U.S. 19- to 25-year-olds are __________ likely than younger or older individuals to __________

A) less; chew tobacco B) more; be inactive C) less; take stimulants D) more; smoke cigarettes