Infants in different cultures may reach different motor milestones like sitting, walking, etc. at different times. Yet, as children they are able to engage in activities requiring comparable levels of motor skills. Which principle of development is illustrated by this example?

A 5-year-old’s father has consented to the child participating in a research study. The child remains well engaged for the first 10 minutes but then seems to become anxious and withdrawn. Bearing ethical principles and standards in mind, what should be the researcher's next step? 

Jasper is interested in knowing whether the environment has more of an effect on intelligence or biology. Which of the following research designs would help Jasper answer this question?

Cyrus has recently moved to Mumbai from his hometown of Indore. He is finding it difficult to make friends in his new school. This can be best understood as the effect of which of the following:

The

case of phenylketonuria (PKU) illustrates that

It would be useful for parental engagement/interaction with premature babies to look different to their engagement/interaction with babies born to term.

Jacky designs a study which involves tracking a group of 60, 65 and 70 year olds for 5 years. Her study is best described as:

Selective attrition is primarily a problem associated with which research design?

Stage theories of development are consistent with which of the following