What will the weather be like in the future? Some people say they can know the weather from animals.

If birds are flying high in the sky, there will be a nice day. When they sit in trees or stay close together, bad weather is on the way. Ants often build their homes on the steep (陡峭的) side just before the rain comes. Cats like to clean their ears before the rain. Chickens make a loud noise and run here and there when the rain is coming. Frogs will stay in the water and make a lot of noise, too. But on a nice day, they are quiet and jump out of the water. Turtles (海龟) often look for higher ground and cows like to lie down when the rain is on the way. 

小题1:How will the weather be if birds are flying high in the sky?

A．Sunny.

B．Windy.

C．Rainy.

D．Snowy.小题2:What do cats like to do before the rain?

A．Clean their feet.

B．Clean their ears.

C．Run everywhere.

D．Stay at home.小题3:How many animals does the passage mention (提到)?

A．Three.

B．Four.

C．Five.

D．Seven.小题4:What’s the best title for the passage?

A．Animals.

B．Animals like different weather.

C．The Weather.

D．Animals and weather.

下图是生物体内核酸的基本组成单位――核苷酸的模式图，相关叙述正确的是

A．若a为核糖，则m，有4种，分别是A、T、G、C

B．若m为鸟嘌呤，则b的名称是鸟嘌呤核糖核苷酸或鸟嘌呤脱氧核苷酸

C．构成人体遗传物质的b共有8种，a有2种，m有5种

D．在HIV和SARS病毒中共可以检测到2种a，5种m，8种b