Eveline Crone studies teenage brains while the teenagers are
O A. reading.
Explanation:
Eveline Crone is a developmental psychologist who studies the growth of the brain in children and teenagers. This she does, by assessing the brains of the teenagers while they are involved in activities where they have to make critical decisions and notices the way they think.
The changes in their brain while they are making these critical decisions while Reading or doing other intellectual activities reveal what the function of the their brain is like.
It's in passive voice.
A good rule of thumb for cases like this is that if it has any variation of the verb "to be" (is, was, were, etc.) it's passive voice.
If you wanted to switch it to active voice you need to get rid of "is", and this is usually done by switching the subject and the object (so while in the original sentence, the race car is the doing the verb, to switch it you'd need to make the sixteen-year-old boy be the one doing the verb). This new sentence would be something like:
The sixteen-year-old boy drove the racecar
Chaucer's view on life is good-humored and hopeful. He had hope that people would be nicer and that the world could be a good place.
