read the passage.\ntesting for concussions\nwhen a patient is suspected of having a concussion, or brain…

read the passage.\ntesting for concussions\nwhen a patient is suspected of having a concussion, or brain injury, doctors often turn to computed tomography, or ct, scans to find out for sure. in a ct scan, a series of x - rays is taken. each one shows an individual \slice\ of the brain, and they can be combined to form a complete three - dimensional picture. because of the amount of radiation patients are exposed to, however, doctors question the use of the scans, especially for children. now researchers have proposed an alternative way of diagnosing head injuries: a simple blood test. the test detects proteins that burst out of brain cells into the bloodstream immediately after an injury. it allows doctors to determine whether a patient has suffered head trauma and needs further treatment.\nwhat is the main, or central, idea of the passage?\na new blood test can identify proteins that are present in the blood following a brain injury.\na new blood test makes it easier—and safer—to detect concussions.\ndoctors commonly use ct scans to test for brain injuries.

read the passage.\ntesting for concussions\nwhen a patient is suspected of having a concussion, or brain injury, doctors often turn to computed tomography, or ct, scans to find out for sure. in a ct scan, a series of x - rays is taken. each one shows an individual \slice\ of the brain, and they can be combined to form a complete three - dimensional picture. because of the amount of radiation patients are exposed to, however, doctors question the use of the scans, especially for children. now researchers have proposed an alternative way of diagnosing head injuries: a simple blood test. the test detects proteins that burst out of brain cells into the bloodstream immediately after an injury. it allows doctors to determine whether a patient has suffered head trauma and needs further treatment.\nwhat is the main, or central, idea of the passage?\na new blood test can identify proteins that are present in the blood following a brain injury.\na new blood test makes it easier—and safer—to detect concussions.\ndoctors commonly use ct scans to test for brain injuries.

Answer

Brief Explanations:

The passage first mentions the use of CT scans (which have radiation exposure issues) for diagnosing concussions. Then it introduces a new blood - test alternative. The new blood - test can detect proteins from brain cells in the bloodstream after an injury, allowing doctors to determine head trauma. This implies that the new blood - test is a better (easier and safer, as CT scans have radiation problems) way to detect concussions compared to CT scans.

Answer:

B. A new blood test makes it easier—and safer—to detect concussions.