Final answer:
In the weighted voting system described, Voter A has the veto power because they control 10 votes, and without their support, the required threshold of 13 votes cannot be met by any combination of the other voters. Thus, the correct answer is A. Voter A.
Step-by-step explanation:
The question asks us to determine who has the power to veto a decision in a weighted voting system where voters A, B, C, and D have different numbers of votes (10, 7, 5, and 3, respectively) and 13 votes are required to pass an issue.
To answer this, we must find out which voter(s) can prevent an issue from passing by withholding their votes. A veto power is held by any voter or group of voters whose votes are necessary for an issue to pass, meaning that without their support, the remaining voters cannot reach the required threshold of 13 votes.
Looking at the weight of each voter's votes, Voter A has the power to veto because A controls 10 votes, which are crucial for getting to 13. Without Voter A's votes, the maximum any combination of the other voters can reach is 7 (B) + 5 (C) + 3 (D) = 15 votes, just meeting the threshold. This implies that if Voter A does not support an issue, the issue cannot pass the required 13 votes margin. Thus, the correct answer is A. Voter A.