Step 1 :The null hypothesis (H0) is a statement of no effect or no difference. It is the hypothesis that the researcher is trying to disprove. In this case, the null hypothesis is that the proportion of blue candies is equal to 27%, as claimed by the candy company.
Step 2 :The alternative hypothesis (H1) is a statement that contradicts the null hypothesis. It is the hypothesis that the researcher believes to be true. In this case, the alternative hypothesis is that the proportion of blue candies is not equal to 27%.
Step 3 :Therefore, the correct answer is A. Final Answer: \[\boxed{\begin{array}{l} H_{0}: p=0.27 \\ H_{1}: p \neq 0.27 \end{array}}\]