SAT Question 916ffe9b: Inference From Sample Statistics And Margin Of Error answer and explanation with Desmos solution

Choice B is correct. It's given that $483$ out of $803$ voters responded that they would vote for Angel Cruz. Therefore, the proportion of voters from the poll who responded they would vote for Angel Cruz is $\frac{483}{803}$. It's also given that there are a total of $6,424$ voters in the election. Therefore, the total number of people who would be expected to vote for Angel Cruz is $6,424\left(\frac{483}{803}\right)$, or $3,864$. Since $3,864$ of the $6,424$ total voters would be expected to vote for Angel Cruz, it follows that $6,424-3,864$, or $2,560$ voters would be expected not to vote for Angel Cruz. The difference in the number of votes for and against Angel Cruz is $3,864-2,560$, or $1,304$ votes. Therefore, if $6,424$ people vote in the election, Angel Cruz would be expected to win by $1,304$ votes.