The relationship between "loud" and "stentorian" is that "stentorian" means extremely loud, often in a commanding or powerful way. It is an intensified or more vivid synonym for "loud."
Checking the options:
- Option (a) "mild : noisy" — these are opposites, not intensifications.
- Option (b) "painful : prickly" — "prickly" is not necessarily more painful; the relationship is different and more descriptive of texture than intensity.
- Option (c) "adjective : descriptive" — this is not a synonym relationship; rather, "descriptive" is a category description, so it does not match.
- Option (d) "bright : resplendent" — "resplendent" means dazzlingly bright or brilliant, making it an intensified synonym of "bright," just as "stentorian" is an intensified synonym of "loud."
Thus, the correct answer is "bright : resplendent."