Answer:
123/20
Explanation:
6.15 = 615/100 = (5×123)/(5×20)
= 123/20
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If choice C is taken to be a typographical error that should be 123/20, then it will be the appropriate choice. Otherwise, the correct answer is not among those offered.
It may be appropriate to ask your teacher to show you how to select the correct answer from those offered.