His ideas are invariably condemned as______by his colleagues.
【正确答案】 C
【答案解析】解析:imaginative“富于想象力的”:ingenious“有创造力的”;impractical“不实际的”;theoretical“理论化的”。根据句意,应该是因为他的观点不切实际,因而被同事谴责,故选C。