An argument is considered sound if it is:

A sound argument is defined as one that meets two essential criteria: it must be valid, meaning that if the premises are true, the conclusion must necessarily follow from them; and all of its premises must actually be true. This combination ensures that not only does the argument follow a logical structure, but it also rests on factual foundations, thereby reinforcing its credibility and strength.

When an argument is valid but has questionable premises, it fails to meet the standard of soundness, as the truth of the premises is not guaranteed. Similarly, an argument characterized as strong and persuasive may be appealing or convincing, but that does not equate to soundness, as it could be based on weak or unsupported premises. Inductive arguments, while they can be strong and persuasive, do not guarantee the truth of their conclusions based on their premises, thereby failing to meet the definition of soundness.

Thus, the correct understanding of a sound argument involves both the logical structure (validity) and the truth of the premises, making option B the most accurate choice concerning the definition of a sound argument.