49.Which event brought the booming of American candy bar business?

• A、The adding of new materials.

• B、The demand in the army during WWI.

• C、The purchase of new machines.

• D、The appearance of smaller candy bars.

I.Phonetics(5 points)
Directions:In each of the following groups of words,there are four underlined letters or let-ter combinations marked A,B,C and D.Compare the underlined parts and iden-tdtify the one that is different from the others in pronunciation.Mark your answer by blackening the corresponding letter on the Answer Sheet.

• A、captain

• B、obtain

• C、contain

• D、retain

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