Respuesta :
The sentence which uses correct parallel structure is (b)Saving is the key to a comfortable old age, and not saving is the key to an anxious one.
What is parallelism?
Parallel structure, also known as parallelism, is a balance between one or more phrases/ clauses which is to be maintained in order to frame grammatically correct sentences. It makes the text easier to read and understand.
Hence, the correct answer is (b)
Learn more about Parallelism on https://brainly.com/question/10517884
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