Multiple choice A pygostyle bone is the: part of pelvic girdle of rabbit last caudal vertebra in bird part of skull of frog last caudal vertebra of frog Reveal answer Fill a bubble to check yourself B Correct answer Explanation The pygostyle is the fused terminal caudal vertebrae in birds, forming a supportive structure for tail feathers and tail muscles. It is not found in frogs or rabbits - their tails contain unfused vertebrae or different skeletal structures.