I'm pretty sure it's "the baby cried" because an independent clause can stand alone and that can stand alone.
A verb is an action. Example: moving, sitting, walking, sleeping.
Creating a dedicated workspace gives you a specific spot you can always focus on your work without distractions, so if you only have 1 hour to finish an assignment, it’s better to do it where you can focus rather than a place where others’ noise can disrupt your focus and productivity.
I think the answer could be c or d. D makes a little more sense though. I hope this helps a little bit.