The objective is to identify a synonym for "Plausible".
To achieve this, we first define "Plausible". It refers to something that seems reasonable or probable, implying it can be believed or accepted as true.
Consider the provided options:
Based on this evaluation, "Believable" is the most fitting synonym for "Plausible," as both convey the idea of being trustworthy or acceptable as true.
Thus, the correct selection is: Believable.