Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fist each of the numbered blanks

Tim Samaras is a storm chaser. His job is to find tornadoes and follow them. When he gets close to a tornado, he puts a special tool (1) ___________a turtle probe on the ground. This tool measures things like a twister’s temperatune, humidity, and wind speed. With this information, Samaras can lean what causes tornadoes to develop. If meteorologists understand this, they can warn people (2) ___________twisters sooner and save lives.

How does Samaras hunt tornadoes? It’s not easy. First, he has to find one. Tornadoes are too small to see using weather satellites. So Samaras can’t rely on these tools to find a twister. (3) ___________, he waits for tornadoes to develop.

Once Samaras sees a tornado, the chase begins. But a tornado is hard to follow. Some tornadoes change (4) ___________several time – for example, moving east and then west and then east again. When Samaras finally gets near a tornado, het puts the turtle probe on the ground. Being this close to twister is (5) ___________. He must get away quickly.