Gross motor skills include activities such as running, whereas fine motor skills include activities such as

A. the effect of any teratogen is dependent on the time of exposure: True in principle (timing affects type of defect), but reducing dose addresses concentration rather than timing.
B. the effect of any teratogen is greater in the last stage of prenatal development: Incorrect: structural malformations are most likely in the embryonic period (weeks 3–8), not necessarily the last stage.
C. the greater the dose of a teratogen, the greater the effect on prenatal development: This describes the dose–response relationship; lowering medication dose reduces fetal exposure and risk.
D. the effect of any teratogen is dependent on the genetic susceptibility of the fetus: Genetic susceptibility does influence outcomes, but the doctor’s immediate action of lowering dose reflects dose–response concerns rather than genetic variability.

A. normative age-graded influences: These are typical developmental changes tied to age (e.g., puberty, starting school), not unusual one-off events.
B. normative life events: The phrase is ambiguous; “normative life events” would imply expected experiences shared by many (not unusual), so it doesn’t match the description of rare, high-impact occurrences.
C. nonnormative life events: Nonnormative events are unexpected or unusual occurrences that have major, often unique, impacts on an individual’s life (e.g., winning a lottery, serious illness) — this matches the description.
D. normative history-graded influences: These are events that affect whole cohorts (e.g., a war, technological revolution) and apply to many people in a generation, not to unusual individual experiences.