Question 30: It was not until 1915 ________ the cinema became an industry.
Structure:
It was + not until + adverb phrase of time/clause + that + clause (QKD): Until…then….
Eg: It was not until I was 30 years old that I got married. (I didn’t get married until I was 30 years old.)
It was not until 2000 that I became a teacher. (It was not until 2000 that I became a teacher.)
=> Answer B (It was not until 1915 that cinema became an industry.)
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