According to the author, why do teens engage in risky behavior?

A. because all humans are drawn to risk-taking
B. because their brain isn’t fully developed
C. because they enjoy dangerous situations.
D. because it’s how they learn about the world

B.

Explanation:

Even without the full authors context, based on common knowledge and process of elimination, B is the most probable answer.

it is an infinitive phrase with a subject.

research question: do the predicted benefits of genetic enhancements outweigh the possible negative consequences of this technology?  

what information do i need to research in order to answer this question?  

-predicted benefits of genetic enhancements

-negative consequences of genetic enhancements

-existing, if any, consequences of the new technology

-possible consequences if the technology is perfected

what sources will have the information?

-scientific research documents or news articles summarizing research

-articles in science and medical journals, magazines, and electronic databases

-books

-experts at genetics: geneticists, scientists, professors

here you go have a nice day