Answer: Option C
Answer: (c)These days most of the students do their assignments with the help of the internet. (a) These days the assignments are being done with the help of the internet by most of the students. (Tense has changed) (b) These days the assignments were being done with the help of the internet. (by the students hasmissing) (c) These days most of the assignments are done with the help of the internet by thestudents. (Correct) (d) These days most of the students are doing their assignments with the help of the internet.(Tense has changed)