完形填空上下文线索 — 英语选择题

完形填空：根据上下文线索，选择最佳选项。 Marco had trained for the marathon for a whole year, yet he felt a sharp pain in his leg at the 30th kilometer. Slowing down, he waved to the crowd with a forced smile, clearly trying to ______ the fact that he could barely walk. A. conceal B. announce C. exaggerate D. confirm