PLAIN: AUSTERE <br/> A. neutral: indifferent <br/> B. clean: sterile <br/> C. alone: gloomy <br/> D. arid: barren <br/> E. fluent: talkative <br/><br/><br/>I chose B. But I am not sure. I hope you will offer a detailed explanation to convince me. <br/><br/><br/>Thank you.<br/><br/>