According to chayko, what % of adults ages 18 to 29 in the united states engage regularly in social networking online?

89% of 18- 29 in the United States engage regularly in Social networking online

Explanation:The number of networking online has increase with more technological innovations where people connect through playing games online , social media sites ,chat areas, classes , and even hangouts. At the age of 18-29 that is when people are more socially active and they actual try all means to get social active at all times. This is the age all's when most individuals are still in school and social networking online is at it peak because it is crucial for one's own life and to get updated with the school work.

the answer might be either a or c. can't be too sure , because i searched the web, but no valid answers came through.

the correct labels are as follows:

a: yellow river

b: himalayan mountains

c: north china plain

d: taklimakan desert