Final answer:
The correct option to replace the underlined portion in the sentence to correct the error in parallel structure is option 3) that he would answer the manager's questions.
Step-by-step explanation:
The correct option to replace the underlined portion in the sentence to correct the error in parallel structure is option 3) that he would answer the manager's questions.
Parallel structure means using the same grammatical structure for similar elements in a sentence. In this case, the parallel structure should be 'that he would answer', which matches the structure of the previous part of the sentence 'that he would answer the questions'.
By choosing option 3), the sentence would be corrected to: 'The survey taker hoped that he would answer the manager's questions.' This maintains parallel structure throughout the sentence.