Answer:
D had 310 points.
The final ranking is: B,A,D,C
Step-by-step explanation:
The problems states that:
There are 115 votes.
Each ballot has a vote for first place, that counts 4 points, a vote for second place, that counts 3 points, a vote for third place, that counts 2 points and a vote for fourth place that counts 1 point. This means that each ballot has 4+3+2+1 = 10 points.
Since there are 115 voters, there are 115 ballots. This means that the total points of A,B,C and D combined must be equal to 115*10 = 1150. So:

We already know that:
A had 320 points, B had 330 points, and C had 190 points.
So:



B had the most points, followed by A, D and C. So the final ranking is: B,A,D,C