阅读理解。

     Wen Jiabao is the premier of the world's most populous (人口众多的) country. But, millions of people

would rather call him "grandpa", Always in plain jackets, he seems an ordinary old man with a kind smile.

     Wen has visited the "left-behind" children before Children's Day. He visited Yang Saike's home,

a primary schoolboy in a village of Xingping County, Shanxi. Yang's parents were working in Fujian,

thousands of kilometers away. He was cared for by his grandparents. His parents fail to go home even

once a year. The premier held Yang in his arms and looked through his exercise book then praised him for

his hard work. When talked with many children and asked them many questions about their schooling and

 life. The premier asked the local governments to do something to protect and care for such children at

home and it their parents in cities not worry about their children.

     But in the face of disasters, he has the power to pull together the whole country. About two hours after

the deadly earthquake hit Sichuan Province, Permier Wen Jiabao was on a plane to the disaster area. Within

two days, he had seen almost all the worst hit cities and towns. The 65-year-old man was seen climbing

over damaged 26 buildings to encourage the trapped kids. And he shed (流泪) tears with sad families and

promised to help rebuild their homes.

1. Why do millions of people in China call Wen "grandpa"?  [ ]

A. Because he is the premier of the world's most populous country.

B. Because he is plain and seems an old ordinary old man with a kind smile.

C. Because he has the power to pull together the whole country.

D. Because he visited almost all the worst hit cities and towns.

2. What's the meaning of "left -behind" children?

HIV的传播途径不包括（）

A.同性或异性间性行为

B.药瘾者共同污染HIV的注射器

C.输血和器官移植

D.母婴垂直传播和围产期传播

E.日常生活的一般接触