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In part A the correlative conjunction ‘not only’ is mentioned. The other half of this is ‘but also’. But in part B we only find ‘but’ which makes it incorrect.

Both parts C and D have errors in their tense. In part C instead of the past tense ‘could’ we need the present tense ‘can’. Similarly, in part D instead of the past tense ‘made’ we need the present tense ‘make’.