30. ________ have made communication faster and easier through the use of e-mail and the Internet is widely recognized. (A) It is that computers (B) That it is computers (C) Computers that (D) That computers

31. Why did the researchers say eggs came after the chicken? (A) Because one of the egg-forming ingredients comes only from the chicken. (B) Because eggshell could be used to make a lot of products. (C) Because eggs are much lighter than the chicken. (D) Because they are British researchers.