Multiple choice general knowledge Smallest mammal small bat vulnerable Kitti's Hog-nosed Bat Bumble bee Berring strait rat Reveal answer Fill a bubble to check yourself B Correct answer Explanation Kitti's Hog-nosed Bat (also called bumblebee bat) is the world's smallest mammal at 29-33mm. 'Small bat' is too vague, while 'Bumble bee' alone refers to an insect.