Answer
(b).
Work Step by Step
The sample proportion is the number of successes divided by the sample size: $\hat{p}=\frac{x}{n}=\frac{225}{757}\approx0.297$
$SE=\sqrt{\frac{\hat{p}(1-\hat{p})}{\sqrt n}}=\sqrt{\frac{0.297(1-0.297)}{757}}\approx0.017$, thus the answer is (b).
