Final answer:
The best sentence to introduce a passage about volunteering is 'Volunteering offers many social and practical advantages that make it a worthwhile pursuit,' as it broadly encapsulates the advantages of volunteering.
Step-by-step explanation:
The sentence that best introduces a passage about volunteering is: a) Volunteering offers many social and practical advantages that make it a worthwhile pursuit. This overarching statement captures the essence of volunteering by suggesting the various benefits it provides, which can then be explored in detail throughout the passage. Such benefits include gaining work experience, creating social networks, learning new skills, and contributing to the community. Specific aspects like political volunteering, using volunteering to gain experience in a field of interest, and listing volunteer work on a resume could be further explained.