题目内容：

If you had a strange sound in your ear，what would you do? One man in Wales who thought he had a fly in his ear called 999，the emergency services number in Britain．And so did a woman who was worried about her green potatoes．Could she make chips with them? Were they poisonous? She didn’t hesitate about calling the local ambulance service to ask．According to a recent report，more than 31，000 non-urgent calls were made to the Welsh Ambulance Service in the last year．

Inappropriate calls are a headache for health professionals everywhere．In the US，prank calls to 911 happen on a daily basis．Many callers use apps which hide their identity．But those who try to be funny shouldn’t be surprised if the police have the last laugh．One man from Colorado was arrested for making more than 1，200 prank calls，according to a report on the US television station KOAA—TV．

People who take these calls are trained to stay calm and keep a straight face，no matter how strange the call sounds．“There’s no way for us to know whether the call is real，accidental or a prank call，”said a public safety worker interviewed by the American TV channel．

The Head of Clinical Services at the Welsh Ambulance Service，Richard Lee，has a warning for prank callers．He says，“When people misuse the service it means our precious time is being taken away from someone who really does need our help．”Indeed，these hotlines are supposed to help the seriously ill or those with a life—threatening injury．You never know，one day，the person who needs assistance could be you or someone in your family．

1.How does the author introduce the topic of the text?

A．By giving examples．   B．By telling a story．

C．By listing figures．   D．By making a comparison．

2.Why are prank calls usually made?

A．To be helpful．    B．To deal with problems．

C．To get praise．    D．To play tricks．

3.What does the phrase“have the last laugh”in Paragraph 2 refer to?

A．Win at last．     B．Never find them．

C．Laugh at them．   D．Know nothing．

4.What does the author intend to suggest in the text?

A．Prank calls are usually easy to identify．

B．Operators feel annoyed by strange callers．

C．Prank calls may cause serious results．

D．Prank callers should be punished by law．