Select the most appropriate synonym of the underlined word in the given…

Concept: A synonym question asks for the option that matches the underlined word's meaning as it is actually used in that sentence, not just any dictionary sense of the word in isolation. "Fulsome", when it modifies words like "praise" or "flattery", carries the established sense of being given in an excessive amount, often to the point of sounding insincere — a different sense from its rarer neutral meaning of "abundant".

Application: In the sentence, "the fulsome praise heaped upon the opposition party" describes praise that goes beyond what the occasion warranted — the speaker’s own surprise ("astounded") signals that the amount of praise exceeded normal bounds. So the underlined word marks a degree of praise that is more than warranted, not praise that is fitting or held in check.

Contrast:

• Excessive — denotes something given in a greater amount than is warranted, which is exactly the degree "fulsome praise" conveys.

• Appropriate — denotes something fitting or suited to the occasion, the opposite of an excessive degree.

• Restrained — denotes something deliberately held back or checked, again the opposite degree.

• Measured — denotes something carefully controlled and proportioned, also the opposite degree.

Result: The correct synonym for "fulsome" here is "Excessive", confirmed by standard dictionary definitions of fulsome (e.g. Oxford Learner’s Dictionary: expressing admiration/approval more than is necessary, in a way that seems insincere).