Aerial photo shows a black-necked crane foraging at the foot of Mount Qomolangma in Xigaze City, southwest China's Tibet Autonomous Region, May 17, 2019. The 8,844.43-meter-high Mt. Qomolangma is the world's highest peak. (Photo: Xinhua)

Photo taken on May 18, 2019 shows the scenery of Mount Qomolangma. The 8,844.43-meter-high Mt. Qomolangma is the world's highest peak. (Photo: Xinhua)

Photo taken on May 18, 2019 shows the scenery of Mount Qomolangma from the base camp in southwest China's Tibet Autonomous Region. The 8,844.43-meter-high Mt. Qomolangma is the world's highest peak. (Photo: Xinhua)

Photo taken on May 18, 2019 shows the scenery of Mount Qomolangma. The 8,844.43-meter-high Mt. Qomolangma is the world's highest peak. (Photo: Xinhua)

Photo taken on May 18, 2019 shows the Rongbuk Monastery at the foot of Mount Qomolangma in southwest China's Tibet Autonomous Region. The 8,844.43-meter-high Mt. Qomolangma is the world's highest peak. (Photo: Xinhua)