What is meant by the first sentence of the second paragraph?

Choose the correct option (A, B, C, or D) to indicate the word whose underlined part differs from the other three in pronunciation in the following question.

Choose the correct option (A, B, C, or D) to indicate the word whose underlined part differs from the other three in pronunciation in the following question.

Choose the correct option (A, B, C, or D) to indicate the word whose underlined part differs from the other three in pronunciation in the following question.

Mark the letter A, B, C, or D to indicate the word that differs from the other three in the position of primary stress in the following question.

Choose one word in A, B, C, or D to complete the following sentences.

Someone who is _______ is hopeful about the future or the success of something in particular.

Choose one word in A, B, C, or D to complete the following sentences.

The medical community continues to make progress in the fight against cancer.

Choose one word in A, B, C, or D to complete the following sentences.

Instead _____ petrol, cars will only run ____ solar energy and electricity.