Read the excerpt from "building skills with video games." playing video games also the brain grow. one group of scientists looked at brains using a mri machine. they looked inside the brains of two groups of people. we’ll call them group a and group b. group a then played video games for thirty minutes each day. group b, on the other hand, didn’t play any video games. after two months, the scientists used the mri again. they could see the difference between the brains of the people in the two groups. group a had more brain growth in an important part of the brain. which sentence provides evidence for the reason why playing some video games can actually make a brain grow? one group of scientists looked at brains using a mri machine. they looked inside the brains of two groups of people. after two months, the scientists used the mri again. group a had more brain growth in an important part of the brain.

The answer is:

Group A had more brain growth in an important part of the brain.

In excerpt from "Building Skills with Video Games," the sentence that provides documentation about video games producing brain growth is the one that directs attention to the group that actually did exhibit evidence of brain expansion because they played video games thirty minutes every day.

The rest of the choices do not specify reasons for brain development - they rather mention the scientists different phases that lead to the final conclusion.

Group A had more brain growth in an important part of the brain. This is the correct option. This is the evidence the scientists got after two months when they carried out the second part of the investigation. In fact, during the first part, the scientists looked into the brain of the group members with a MRI  (Magnetic resonance imaging ). Then, after two months, they looked into their brains again and saw the difference between this group and group B. Group B did not play any video game.

These options are wrong:

- One group of scientists looked at brains using a MRI machine. This does not tell the reason since there is not any evidence; it just describes the procedure of the study.

-They looked inside the brains of two groups of people. The scientists studied the brains but did not see anything ,yet.

-After two months, the scientists used the MRI again. This refers to the device the scientists used during a second step of their study.

the illustration   that would give a reader a clear understanding of the text is a picture of men constructing the frame of a building.the frame is made of iron bars. the text describes the job of blacksmiths'. these were very organised and they had different names: "the driver" and "the heater". the text describes the way in which these men worked ; they worked iron pieces as if they were playing a sport. in fact, the text wants to show the men's skills. the text also puts some emphasis on the use of '' rivets'' in construction. this kind of nails were not always used in the construction of manhattan.

some examples:

"and with an underhand toss he hurled the smoking rivet straight at the catcher, who caught it in mid-air in his catching can." men's skills

"when the driver was ready for a new " the emphasis on the rivet ( special nail used in construction).

" it against a beam to remove any cinders, and jammed it into the waiting hole. " the emphasis on the rivet.

harlem's  cotton club boasted the talents of duke ellington. singers such as bessie smith and billie holiday popularized blues and jazz vocals. jelly roll morton and louis armstrong drew huge audiences as white americans as well as african americans caught jazz fever.