Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 19 to 24.

Today, childhood is spent mostly indoors watching television, playing video games and (19) ______ the Internet. When children go outside, it tends to be for scheduled events like a soccer match or a fishing derby. These events are held under the watch of adults.
The shift to an indoor childhood has accelerated in (20) ______ past decade, with a significant decline in spontaneous outdoor activities such as bike riding, swimming and touch football, according to some studies by the National Sporting Goods Association. (21) ______, a child is six times more likely to play a video game on a typical day than to ride a bike.
Indoor childhood has brought about some changes which can be seen in children's bodies. In the 1960s, 4% of kids were obese. Today, 16% are overweight. The changes can also be seen in their (22) ______. Studies indicate that children (23) ______ spend plenty of time outdoors have a longer attention span than those who watch (24) ______ television and play video games.