A substantial hike in the top rate of income tax would not solve this problem but merely aggravate the nation's already waning support.
【正确答案】 C
【答案解析】解析:depreciating“贬低,降职”;warning“警告,通知”;declining“下降”;startling“震惊”。wane意为“衰退,减弱”,结合题意,故选C。