When we are young, we learn that tigers and sharks are dangerous animals. We might be scared of them because they are big and powerful. As we get older, however, we learn that sometimes the most dangerous animals are also the smallest ones. In fact, the animal that kills the most people every year is one that you have probably killed many times: the mosquito.

While it may seem that all mosquitoes are biters, this is not actually the case. Male mosquitoes eat plant nectar. On the other hand, female mosquitoes feed on animal blood. They need this blood to live and produce eggs. When a female mosquito bites a human being, it injects a small amount of saliva into his/her blood. This saliva may or may not contain a deadly disease. Therefore, the result of the bite can be as minor as an itchy bump or as serious as death.

Because a mosquito can bite many people in the course of its life, it can carry diseases from one person to another very easily. Two of the most deadly diseases carried by mosquitoes are malaria and yellow fever. More than 700 million people become sick from these diseases every year. At least 2 million of these people will die as a consequence.

Many scientists are working on safer and better forms of killing mosquitoes, but so far, there is no sure way to protect everyone in the world from their deadly bites. Mosquito nets can be placed over beds to protect people against being bitten. These nets help people stay safe at night, but they do not kill any mosquitoes. However, mosquitoes have many natural enemies like bats, birds, dragonflies, and certain kinds of fish, so bringing more of these animals into places where mosquitoes live might help to cut down the amount of mosquitoes in that area. This is a natural solution, but it does not always work very well. Mosquitoes can also be killed with poisons or sprays. Even though these sprays kill mosquitoes, they may also harm other plants or animals.

Internet: <www.englishforeveryone.org> (adapted).

Based on text above, judge the following item.

Tigers and sharks are dangerous to young people, but not to older people.