Answer:
1)Junk food has high quantity of preservatives that is harmful for health.
2)Computing junk food can lead to obesity.
A and D are grammatically correct! B and C are 100% incorrect.
In A, you can write "You are quite a..." as "You're quiet a...", but in D ,i don't see an error. So it's a 50-50 in my opinion.
I'm not a 100% sure on the right answer, but i can assure you that the answer is either A or D. Hope it helps!
A nun should be modest, had to have poverty, and pity. Chaucer describes the nun in the opposite way to show us, how the nun Prioress had all the characteristics that a nun should not have. She was a nun modest, well educated and with good manners.