7. When do CAPTCHAs usually appear?
(A) When your computer has been invaded by a bot.
(B) When you log into sites like Google or Yahoo.
(C) When you move through different video game level.
(D) When you use your credit card to buy something online.

3. Which of the following symptoms is NOT mentioned as a result of a sunburn? (A) Lightheadedness. (B) Nausea. (C) Sleepiness. (D) Muscle cramps.

4. Which of these activities should not be engaged in on a summer day? (A) Outdoor tennis. (B) Barbecuing in one's garage. (C) Picnicking under a tree. (D) Hiking in the woods.

5. This passage serves as (A) a commercial for suntan lotion. (B) a lecture on dermatology. (C) health advice. (D) a lecture on anatomy.

6. What has happened as CAPTCHAs have gotten more challenging? (A) Cyber crime has become less prevalent. (B) Solving them has become more difficult for users. (C) Websites have required multiple CAPTCHAs. (D) More computer users have downloaded viruses.

8. What solution do spammers use to deal with CAPTHAs? (A) They send virus email. (B) They pay low wages to less fortunate people. (C) They hack into famous web pages. (D) They break down the social network.

9. How have CAPTCHAs been made more challenging? (A) By making some of the letters backwards. (B) By using forms of animals and other objects. (C) By drawing pictures about person. (D) By asking private questions.

10. Based on the passage, which of the following statements is true? (A) Spammers wrote programs to decipher CAPTCHAs. (B) Overall Internet usage has increased due to CAPTCHAs. (C) People stop using the web because of CAPTCHAs. (D) The success rates for first time users of CAPTCHs have increased. 

1. In an experimental biological research, what is the function of a controlled experiment? (A)A carefully recorded result (B)A repeat of an experiment (C)An experiment that all variables are kept constant (D)A group that is designed to contrast with an experimental group with a treatment (E)An experimental group for testing the variation

2. Charles Darwin proposed which one below in evolutionary biology? (A)Genetic drift (B)Gene flow (C)Natural selection (D)Mutation (E)Island biogeography

3. Water is the molecule that makes the life on the earth possible. Which on below did NOT describe its property correctly? (A)The property of cohesion of the water molecules is due to covalent bonds. (B)Water molecules are the most abundant molecules on the surface of the Earth. (C)Water is an excellent solvent of life. (D)Water has high specific heat thus stabilizes the thermo-dynamics in organisms. (E)Water molecules are constantly moving in a liquid status.