题目内容：

    As Wilson Guarin watched the helicopter roaring above, he wondered if the men being lifted into the sky felt the risk had been worth it.

Moments earlier, Guarin and his children had hiked to Hermit Falls in Angeles National Forest, one of the most popular waterfalls in the Los Angeles area. Soon after they arrived, they saw a man dislocate his shoulder when he jumped into the rock pool at the base of Hermit Falls.  Less than a minute later, another man jumped and appeared to break both his legs. Guarin said the cliff jumpers' intentions were obvious. They wanted to get a video of themselves and post it to social media.

A thirst among hikers, often inexperienced and under-prepared, to collect "likes" and shares on Instagram and other social media sites has led to a significant increase in rescue missions by first responders.

The Los Angeles County Sheriff' s Department's Search and Rescue teams conducted 681 missions in 2017, the largest number in five years. It' s a 38% increase from the 491 rescues they did in 2013.

The teams' leaders say the single largest factor for that increase is people posting videos of extreme activities online. Then, without any thought about the difficulty, others try to recreate their own 15-second version of glory.

On Instagram, posts from visitors venturing to waterfalls and swimming holes in Angeles National Forest and other recreation areas show hikers changed into models, striking seemingly the same poses in the same places.

We shouldn't discourage people from enjoying the outdoors. But many accidents are avoidable and happen either when people go off trail or ignore official warnings about an area being closed and visit anyway.

Guarin still thinks about the two men he watched hitching helicopter rides to a hospital. "You get concerned about what people are willing to do - to not have fun. It's risking everything for no reason. "

Well, there are the "likes".

1.What happened to the two jumpers'?

A.They both got badly injured.

B.They were trapped in a rock pool.

C.They were rescued by the Guarins.

D.They were caught in an air crash.

2.What is the main reason for the increase in the number of rescues?

A.Hikers are inexperienced and under-prepared.

B.Helicopters are readily available in more areas.

C.Travelers go off trail or ignore official warnings.

D.More people share their extreme activities online.

3.What do the figures imply in paragraph 4?

A.More social rescues are timely and effective.

B.More attention is paid from the social media.

C.More people raise the awareness of self-defense.

D.More public resources are obviously being occupied.

4.What does Guarin think of the jumpers' action?

A.It is not a wise thing to do.

B.It is their own version of glory

C.Watching it online is a lot of fun.

D.Getting "likes" makes it worthwhile.