Singer Ariana Grande (C) performs “Side by Side” during the 2016 American Music Awards in Los Angeles, California, U.S., November 20, 2016. (Photo by Mario Anzuoni/Reuters)

A supporter of China's President Xi Jinping waits on the Mall for him to pass during his ceremonial welcome, in London, Britain, October 20, 2015. Xi is on a State visit to Britain. (Photo by Peter Nicholls/Reuters)

Israeli soldiers play the parts of wounded civilians during a drill simulating a toxic spill from an attack on a train in Beersheba, southern Israel, 13 January 2016, as Home Front medical teams, fire fighters and police carry out rescue operations. The large scale drill is the concluding exercise of the Fourth International Conference on Healthcare System Preparedness and Response to Emergencies and Disasters and includes some 200 of the world's experts on health system readiness from around the world. The conference is dealing with all types of medical emergencies from terrorist attacks to natural disasters. (Photo by Jim Hollander/EPA)

An abandoned tank left by Boko Haram, February 20, 2016, seen on the road to Michika, Nigeria – a town formerly occupied by the insurgents. On April 14, 2014, 300 schoolgirls in the Chibok village in Nigeria were kidnapped by the terrorist group, Boko Haram. Two years later, the majority of these girls are still missing. According to the Global Terrorism Index Report 2015, Boko Haram, which operates mainly in Nigeria, has become the most deadly terrorist group in the world. (Photo by Danielle Villasana)

A gaggle of goslings huddle together under the protective wing of a parent along the bank of the Deschutes River as a heavy downpour passes through Bend, Oregon, late Wednesday, April, 20, 2106 afternoon. (Photo by Ryan Brennecke/The Bulletin via AP Photo)

A child sleeps under a table at the Jorkpan market in Sinkor district in Monrovia, Liberia on May 2, 2016. (Photo by Marco Longari/AFP Photo)

In this Tuesday, February 28, 2017 photo, 3-month-old Junior Alexis Patino, son of FARC rebel Deisy Garcia, sleeps next to his mother's weapon at a rebel camp in a demobilization zone in La Carmelita, in Colombia's southwestern Putumayo state. Amid the makeshift tents and communal kitchens where Colombia's largest rebel army is preparing to lay down its weapons, a new sound is emerging: the cries of babies. (Photo by Fernando Vergara/AP Photo)

Actress and model Charlotte McKinney attends the grand opening of NightSwim at Encore Beach Club at Wynn Las Vegas on May 5, 2017 in Las Vegas, Nevada. (Photo by David Becker/Getty Images for Wynn Las Vegas)