1. (2022高二上·西宁期中) 阅读下面短文，从短文后各题所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项。

On Thursday morning, two teenage boys were rescued by a drone (无人机) in Australia while lifeguards were still training to use the machine.

The1, aged 15-17, got into difficulties about 700 feet off the coast of Lennox Head, New South Wales (NSW). A passer-by saw them 2 in dangerous waves. Lifesavers3 sent the drone to drop a lifeboat, and the pair made their way safely to the4.

The drone, known as "Little Riper", was actually not 5 to be saving anyone just yet—lifeguards were being trained to6 the machine. When a call came through about the swimmers in7 the drone happened to be nearby.

Jai Sheridan was the lifeguard who 8 the drone. He described the experience as9. "The Little Ripper10 proved itself today. It is a highly efficient piece of lifesaving equipment. I was11the drone when the alarm was raised. I directed it towards the swimmers and dropped the 12. With its support they made their way to safety. They were 13, but not hurt. The teens were saved in just 70 seconds with the drone—while a lifeguard would have taken up to six minutes to 14 the rescue. "

John Barilaro, an official of the state, 15 the rescue as historic. "It was the world's 16 rescue by the unmanned airplane, " he said. "Never before has a drone been used to 17 swimmers like this. "

Last December, the NSW state government 18 some "Little Ripper" drones for 247, 000 pounds. 19 some are designed to spot sharks, others are 20with lifeboats, alarms and loudspeakers. "It was money well spent," said John Barilaro.