A 52-year-old Nepalese man reached the top of Mount Everest for the 21st time on Wednesday, breaking a record he set last year for the number of ascents of the world's tallest peak, a tourism official ministry said.Apa Sherpa first climbed Everest in 1990 while helping international expeditions climb the mountain.Since 2008, he has been climbing Everest as part of an expedition to highlight the effects of climate change and to collect trash on the mountains.He started from Camp IV at an altitude of 7,950 meters with five other climbers on Tuesday night and reached on Wednesday morning, according to Asian Trekking, which organized the expedition.Sherpa is the climbing leader of the expedition, which collects trash such as oxygen cylinders, tent poles, tents and other mountaineering equipment from the mountain.Source: CNN