Why might someone agree to translate a document for...

Câu hỏi: Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.
THE POWER OF CROWDSOURCING.
There is a famous old saying that when trying to solve a problem "two heads are better than one". Yet until recently, businesses would often rely on one key person to get important tasks done. But thanks to a
phenomenon called crowdsourcing, more and more companies are allowing their consumers to have their say when designing new products.
The term "crowd sourcing" refers to the process of outsourcing jobs which were once done by a single person to a large group (or a crowd) of people. In the past, crowdsourcing wasn't practical, as it was impossible to gather thousands of like-minded people together to share opinions. Now, thanks to the Internet, online forums, and social media, this isn't a difficult task at all.
There are many important applications for crowdsourcing in business. For example, if a small business was looking to develop a business logo, it might employ a single designer and hope for the best. However, with crowdsourcing, companies can specify some guidelines about their project, set a budget, and start a design contest online. Within hours, they will likely receive hundreds of designers sending them logos. In the end, they can choose the design they like best and the winner will get compensated.
Crowdsourcing has other applications as well. A website called Duolingo is using crowdsourcing to translate documents into different languages. It offers free lessons to language learners. As part of their tests, users translate lines to test their knowledge. Then, a computer program will analyze thousands of test results for consistency and arrange an accurate translation.
Not everyone is sold on crowdsourcing, though. In many cases, it may be better to rely on the opinion of a few specialized professionals than information from a crowd. For instance, it makes more sense to trust the opinion of one top doctor than to take the advice of 1,000 random people regarding a health issue. Another criticism is the low wage that crowdworkers usually receive. Since crowdworkers are freelancers and not employees, they can be paid less than minimum wage. Whether you love or hate crowdsourcing, it appears to be here to stay. So before you make any financial judgements, consider following the crowd and give crowdsourcing a try.
Why might someone agree to translate a document for Duolingo?
A. They might get paid lots of money.
B. It will help them get a good job in the future.
C. Duolingo will let them use crowdsourcing for free.
D. It is a part of their free language course.