For the past 30 years, researchers have been experimenting with hooking a human brain up to a computer. they call it a brain-computer interface (or bci), and they have been making progress over the past 10 years. in 1999, doctors were able to place a bci in the brain of a man who had suffered a stroke. the bci interpreted his "thoughts" so that he could use a mouse to move a cursor around on a computer screen to type out his words. this device allowed the man to "speak" with his family and friends even after the stroke had damaged most of his brain function. in 2004, doctors placed a bci in the brain of a paralyzed man, allowing him to use a mouse to move a cursor. he could also type on a keyboard and play video games. he could even operate a robotic arm. this leap in technology will allow future scientists combine their knowledge of the human body with technology.

which of the following is the best way to paraphrase this paragraph?
a.
in 10 years, everyone will have a brain-computer interface because researchers are making a lot of progress.
b.
brain-computer interfaces work when they are connected to the brains of disabled people to allow the people to communicate.
c.
scientists and doctors have been researching brain-computer interfaces for the past 10 years and experimented with them.
d.
researchers have had success in connecting a human brain with a computer using a brain-computer interface.