根据以下材料，回答1-20题
Could a hug a day keep the doctor away? The answer may be a resounding"'yes！" 1 helping you feel close and 2 to people you care about, it turns out that hugs can bring a3 of health benefits to your body and mind.Believe it or not, a warm embrace might even help you 4 getting sick this winter.
In a recent study 5over 400 healthy adults,researchers from Carnegie Mellon University in Pennsylvania examined the effects of perceived social support and the receipt of hugs6 the participants' susceptibility to developing the common cold after being7 to the virus.People who perceived greater social support were less likely to come 8 with a cold, and there searchers 9 that the stress-reducing effects of hugging 10 about 32 percent of that beneficial effect.11among those who got a cold, the ones who felt greater social support and received more frequent hugs had less severe 12
. "Hugging protects people who are under stress from the 13 risk for colds that's usually 14 with stress," notes Sheldon Cohen, a professor of psychology at Carnegie.Hugging "is a marker of intimacy and helps 15 the feeling that others are there to help16 difficulty."
Some experts 17 the stress-reducing,health-related benefits of hugging to the release of oxytocin, often called "the bonding hormone" 18 it promotes attachment in relationships, including that between mothers and their newborn babies. Oxytocin is made primarily in the central lower part of the brain,and some of it is released into the bloodstream.But some of it 19 in the brain,where it 20 mood, behavior and physiology.
第2题选择是_____.

A connected

B restricted

C equal

D inferior