Questions 11-18 refer to the following passage.
 Rescarch suggests that at Icast 64 percent of people now spend up to four hours daily of leisuretime in front of a screen. Just as TV watching has been linked to higher rates of obesity and diabetes,this extra __11__ . time is bad news for our health.  1. CHOOSE OUTDOOR A CTIVITIES OVER TECHNOLOGY        When you're at home, make it a rule that you can't be online if the sun is shining._12__. youhave to go for a walk, ride abike, swim or get s some other kind of healthy physical activity for at least anhour before you can pull out your phone or tablet, or take a seat at the computer. This rule should __13__. everyone in your household.  2. LIMIT SOCIAL MEDIA USE Social networks have transformed computer and mobile use for people of all ages. Whether it'sFacebook, Twitter, Instagram or Snapchat, __14.__ limits on the amount of time you spend on socialmedia. Avoid aimless browsing and give your time online a purpose: research holidays or catch up onthe news of the day. Then_15._3. SET ASIDE READING TIME
 Challenge yourself__16.__ read at least 30 pages of a great book before you check yourcomputer or mobile device. Pick the right reading material and you'll soon find you've discovered anenjoyable __17__.
【題組】11.
(A) sedimentary
(B) arbitrary
(C) sedentary
(D) rudimentary