Answer to Question 1
D
Answer to Question 2
During prenatal development, the head accounts for half of the body length, an illustration of the cephalocaudal trend. The trunk then grows fastest during the first year of life, reducing the relative size of the head. Next, the legs begin to grow rapidly from the first birthday to the adolescent growth spurt. By the time we reach adulthood, the legs--not the head--account for half of our height.
Another proportional change in the body occurs in the growth pattern for the arms and legs versus the hands and feet. Throughout childhood, the arms and legs tend to grow faster and seem proportionally large, an indication of the proximodistal growth trend. However, just before puberty, this trend reverses, and the hands and feet begin to grow rapidly to become the first body parts to reach normal adult proportions.
