When children spend more time with people who have different perspectives on the world than does the child, the child tends to experience a reduction in ____

The body's first shield from foreign invaders is

A) the skin. B) antigens. C) pathogens. D) white blood cells.

Which of the following is LEAST likely to be used as a dependent variable in a human factors experiment?

a. error rate b. time to complete a task c. performance on a secondary task d. the participants' subjective estimates of their performance