A rescue dog is seen during an international Mission Readiness Test for dogs in Jastrebarsko, Croatia, Oct. 20, 2019. The test was attended by teams from all over Europe. (Tomislav Miletic/Pixsell via Xinhua)

A rescue dog is seen during an international Mission Readiness Test for dogs in Jastrebarsko, Croatia, Oct. 20, 2019. The test was attended by teams from all over Europe. (Tomislav Miletic/Pixsell via Xinhua)

A rescue dog is seen during an international Mission Readiness Test for dogs in Jastrebarsko, Croatia, Oct. 20, 2019. The test was attended by teams from all over Europe. (Tomislav Miletic/Pixsell via Xinhua)

A rescue dog is seen during an international Mission Readiness Test for dogs in Jastrebarsko, Croatia, Oct. 20, 2019. The test was attended by teams from all over Europe. (Tomislav Miletic/Pixsell via Xinhua)