Hi there..here's my opinion:
When answering a multiple-choice question, it's important to read every response before making a choice because, you'll have to go through every answer option and see which one is correct...for example:
2 + ? = 19 | You'll add 2 + 14 = 16
A. 14 C. 11 | You'll add 2 + 11 = 13
B. 18 D. 17 | You'll add 2 + 18 = 20
| Then, you'll add 2 + 17 = 19
Since you've went through every answer choice, you found that 2 + 17 = 19. Hope this helped!