Scientists have long questioned how far bees travel to collect food. They believe that bees can fly as far as 10 kilometers if necessary, though most of the time, bees don’t go that far.

To find out the answer, some scientists used small codes called “April Tags” to track bees. These codes are similar to QR codes (二维码). They are easy for cameras to follow, even without enough light, and they don’t hurt the bees.

The scientists put the sensors (传感器) on 600 young bees every two weeks. Over the spring and summer, they followed more than 32,000 bees in six hives (蜂房). By putting a camera and a small computer on each hive, the scientists could tell when the bees with sensors left and returned.

The scientists found that most bee trips outside the hive took just one to four minutes—probably for quick jobs like checking the weather. Longer trips were usually under 20 minutes. But about one third of the bees took trips over two hours. This might mean the bees were making longer trips to collect food. The scientists also found that it took the bees more time to collect food when there were not enough flowers around.

Bees use special “dances” to communicate with each other about where to collect food. Now the scientists want to know the relationship between their new tracking information and these special “dances”. They plan to teach beekeepers and other scientists how to use this new tracking way.

1. 3．What can we learn from the passage?（推理判断）

A    These codes are dangerous to the bees.

B    Scientists studied the bees very carefully.

C    All the bees took trips longer than two hours.

D    Beekeepers have used this new tracking way.

2. 4．Who might find this passage most helpful?（推理判断）

A    Students good at math.

B    Students interested in the Internet.

C    Students good at dancing.

D    Students interested in natural science.