Correct Answer:
C. Had worked
Had worked is the correct answer because the sentence is an example of the third conditional, which describes an imaginary or unreal situation in the past and its possible consequence. The speaker suggests that she did not work hard enough and, as a result, she did not pass the examination. The third conditional is formed using If + Past Perfect, would have + Past Participle. Therefore, the complete sentence is: \"If she had worked hard, she would have passed the exam.\"
Why are the other options incorrect?
- Has worked: This is the present perfect tense. It does not follow the required third conditional structure.
- Worked: This is the simple past tense, commonly used in the if-clause of a second conditional sentence.
- Had worked: This is the past perfect tense and correctly completes the if-clause of the third conditional.
- Had been worked: This is an incorrect passive construction in this context. The verb \"work\" is used intransitively here.
Remember: Third conditional sentences are commonly used in English grammar tests, FPSC, PPSC, NTS and other competitive examinations.