The correct answer is D. Both A and C are the effects of a DUI.
I am going to assume you are talking about emotion. If that is the case then it's better to let it all out, let the wall fall.
Pure determination and hardwork
Find a suitable environment.
Create a study routine.
Block distracting websites + apps on your phone, tablet, and computer.
Divide up + space out study sessions(give yourself breaks when you them)
Find the best tools.
Focus on skills, not grades!!!
Schedule your time and tasks!
Hope this helped!! You’re not alone sometimes it’s hard for me to focus or stay steady since I have bad anxiety and depression so if you need anyone to talk to I’m all ears