Theo quan niệm tiến hóa hiện đại, phát biểu nào sau đây đúng?

A. Mọi biến dị trong quần thể đều là nguyên liệu của quá trình tiến hóa

B. Các quần thể sinh vật chỉ chịu tác động của chọn lọc tự nhiên khi điều kiện sống thay đổi

C. Những quần thể cùng loài sống cách li với nhau về mặt địa lý mặc dù không có tác động của các nhân tố tiến hóa vẫn có thể dẫn đến hình thành loài mới

D. Khi các quần thể khác nhau cùng sống trong một khu vực địa lý, các cá thể của chúng giao phối với nhau sinh con lai bất thụ thì có thể xem đây là dấu hiệu của cách li sinh sản

Read the following passage and mark the letter A, B, c, or D on your answer sheet to indicate the correct answer to each of the following questions.

It is commonly believed in the United States that school is where people go to get an education. Nevertheless, it has been said that today children interrupt their education to go to school. The distinction between schooling and education implied by this remark is important.

Education is much more open-ended and all- inclusive than schooling. Education knows no bounds. It can take place anywhere, whether in the shower or on the job, whether in a kitchen or on a tractor. It includes both the formal learning that takes place in schools and the whole universe of informal learning. The agents of education can range from a revered grandparent to the people debating politics on the radio, from a child to a distingguished scientist. Whereas schooling has a certain predictabillity, education quite oftcr produces surprises. A chance conversation with a stranger may lead person to discover how little is known of other religions. People arc engaged in education from infancy on. Education, then it is a very broad, inclusive term. It is a lifelong process, a process that starts long before the start of school, and one that should be an integral part of one ‘s entire life. Schooling, on the other hand, is a specific, formalized process, whose general pattern varies little from one setting to the next. Throughout a country, children arrive at school at approximately the same time, take assigned seats, are taught by an adult, use similar textbooks, do homework, take exams, and so on. The slices of reality that are to be learned, whether they are the alphabet or an understanding of the workings of government, have usually been limited by the boundaries of the subject being taught. For example, high school students know that they are not likely to find out in their classes the truth about political problems in their communities or what the newest filmmakers are experimenting with. There are definite condition surrounding the formalized process of schooling.

Question: The word ’’they” refers to______

A. slices of reality

B. similar textbooks

C. boundaries

D. Seats

Trong không gian Oxyz, cho mặt cầu (S) x - 1 2 + y + 3 2 + z - 4 2 = 4 . Tọa độ tâm I và bán kính R của mặt cầu (S) là