Q2: They (get paid or are getting paid) weekly

Hello again... 

I did an online exercise in which I found this sentence: 

-  Currently, they ________ (a. are working, b. work, c. either is possible) on a new project for which they  _______ (a. get paid, b. are getting paid, c. either is possible) weekly. 

I filled the first gap with 'are working' and I was correct as per the site. But I was marked wrong when I filled the second gap with option 'b', i.e., are getting. Teachers, was it really incorrect to choose 'are getting paid' for the second gap? I think It shouldn't have been incorrect, because they are getting paid weekly for the project that is currently in progress, so both 'working on the project' and 'getting paid weekly' are temporary or limited-in-time situations. What would you say on this, please? 

Thank you all.