People of pro-government groups, with Russian flags, dance marching through downtown Moscow to mark People's Unity Day, a public holiday, in Russia, on Tuesday, November 4, 2014. Russia marks National Unity Day on November 4 to celebrate the defeat of Polish invaders in 1612. (Photo by Ivan Sekretarev/AP Photo)

A woman wearing a scarf to cover her face looks on as she waits for a passenger bus on a smoggy morning in New Delhi, India, November 8, 2017. The Great Smog of Delhi is an ongoing severe air-pollution event in New Delhi and adjoining areas in the National Capital Territory of India, in November 2017. Air pollution at this time peaked on both PM 2.5 and PM 10 levels. It has been reported as one of the worst levels of air quality in Delhi since 1999. (Photo by Saumya Khandelwal/Reuters)

A woman carrying a basket of papayas while walking through a vegetable market in Bangkok, Thailand November 11, 2011. (Photo by Kerek Wongsa/Reuters)

Nuns from the United States dance as they wait for the Holy Mass with Pope Francis (not seen) at the Campus Misericordiae in Brzegi, Poland, 31 July 2016. Today Pope Francis will celebrate the holy mass ending the World Youth Day 2016 in Poland. (Photo by Marcin Obara/EPA)

José Pereira de Souza plays an accordion as actress and model Tatiana Melo gives a television interview in Feira Nordestina outside of the Olympic periphery on Wednesday, August 17, 2016. (Photo by Aaron Ontiveroz/The Denver Post)

Migrants prepare their food outside shelters in a muddy field called the Grande-Synthe jungle, near Dunkirk, northern France, January 12, 2016. The Grande-Synthe jungle is a camp of tents and makeshift shelters where migrants and asylum seekers from Irak, Kurdistan and Syria gather. (Photo by Benoit Tessier/Reuters)

Professional conceptual category winner. Greetings from Mars, by Julien Mauve, France. Mauve says: “I have always wondered what it would be like to discover a totally different world ... and to photograph it for the first time as if I was Ansel Adams. So I came up with this project, which is about space exploration and discovery. But it’s also about our behavior in front of landscapes and how we create pictures that will share our personal story with the world”. (Photo by Julien Mauve)

Muhannad al-Kadiri (R),18, and Ibrahim Eid, 16, demonstrate their Parkour skills over a military vehicle in the rebel-held city of Inkhil, west of Deraa, Syria, February 4, 2017. (Photo by Alaa Al-Faqir/Reuters)