Directions : Read the following passages and choose the best alternatives.
Passage 1 Items 1-5
Mother’s Questions
     Questions make up as much as 40 percent of what mothers say to young children, according to studies cited by psychologists Jone Leifer and Michael Lewis of the Educational Testing Service. These researchers have taken a psychologist’s look at mothers’ questions and connection to the way children learn to use language.
Mothers most often ask questions to find out what words their children know, for example, “What’s that?” when a child takes a toy from the shelf. These questions contrast with requests for information, such as asking a child with his back turned. “What are you doing?” or directive questions which are really orders in question form.
     These kinds of questions turned up in the conversation for four pairs of middle-class mothers and children that the researchers intermittently videotaped over an eight-month period. The three boys and one girl ranged in age from 18 to 23 months at the start of the experiment.
     During the eight months, of children, a girl and a boy, increased the average number of words they spoke at one time from 1 to 2.7 and 3.3, respectively, while the other two increased their average speeches by only 0.2 and 0.5 words. The mothers of the two children who improve the most had asked fewer questions as the months passed, while the other mothers had increased their questions. The researchers do not yet know whether the early question-asking helped the children who learned rapidly, or just accompanied learning that was rapid for other reasons.

Why was the research mentioned here undertaken?