In describing his dog's sexual behaviors, Frank says his dog is the "stud" of the local neighborhood, describing how his dog regularly visits nearby female dogs. Frank's explanation shows

What is the process in which high-frequency sound waves scan the mother's womb to produce an image of the unborn baby, whose size and shape can then be assessed?

a) first-trimester screen b) ultrasound sonography c) amniocentesis d) chorionic villus sampling (CVS)

Which one of the following is NOT one of the three models of illness described in your text?

a. chronic b. acute c. reactive d. cyclic