Elizabeth Mills jumps in front of the Conservative Political Action Conference (CPAC) sign at National Harbor, Md., February 23, 2018. (Photo by Joshua Roberts/Reuters)

A Hong Kong Correctional Services Dog Unit (CSDU) officer demonstrates training at the CSDU training facility in Stanley, Hong Kong, China, 27 February 2018. The Hong Kong CSDU consists of 29 staff members divided across six dog teams. According to the department's latest figure from 2017, the average daily penal population of Hong Kong was 8,529. (Photo by Jérôme Favre/EPA/EFE)

Trainer Lawney Hill poses for a photograph as she wears tights over her face to keep out the cold after taking her horses out on the all-weather gallops in Tetsworth, Britain, March 2, 2018. (Photo by Eddie Keogh/Reuters)

Comedian Chevy Chase gets a kiss on his ear from co-star Benji as the two held a press conference in Los Angeles, September 6, 1979, at which they announced their up-coming movie “Oh Heavenly Dog” would begin filming this month. The film will be shot on location in London, Berlin and Paris; but due to British quarantine laws a double will be used for Benji at the London location. (Photo by Nick Ut/AP Photo)

A bride waits to take her wedding vow during a mass marriage ceremony in which, according to its organisers, 111 Muslim couples took their wedding vows, in Ahmedabad, India January 26, 2017. (Photo by Amit Dave/Reuters)

People smear black ash with hands onto each other to wish for good luck and fortune during a traditional festival of the Yi ethnic minority in Qiubei County, Yunnan province, China July 18, 2017. (Photo by Ren Dong/Reuters/CNS)

People wash in water from a broken water pipeline on the outskirts of Kolkata, India, March 30, 2016. (Photo by Rupak De Chowdhuri/Reuters)

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)