A. radical
B. active
C. young
D. cheerful
Dour : relentlessly severe, stern, or gloomy in manner or appearance.
Radical : (especially of change or action) relating to or affecting the fundamental nature of something; far-reaching or thorough.
Active : engaging or ready to engage in physically energetic pursuits.
Young : having lived or existed for only a short time.
Cheerful : noticeably happy and optimistic.
Antonym of Dour is Cheerful
