The correct sentence structure should be "No matter what I do, I can't make her happy," where the subject 'I' directly follows 'what.' This is a standard phrase structure used in English.
- Option (a) is incorrect because “should I do†is a question structure, and it's inappropriate in this sentence.
- Option (b) is incorrect as “will I do†doesn't fit the conditional structure implied in the sentence.
- Option (d) uses the past tense "did" incorrectly because the statement describes a general scenario.
Thus, the correct sentence is “No matter what I do, I can't make her happy.â€