Fused vertebrae in human are I. Sacral II. Coccygeal III. Thoracic IV. Cervical V. Lumber
a)	I and II	b)	III and IV	c)	IV and V	d)	II and V

(a)

Sacral and coccygeal (caudal) vertebrae are fused vertebrae in human beings

Sacral vertebrae First five sacral vertebrae gets fused to form sacrum. It is a strong and short supporting pelvic girdle as it (sacrum) articulates with the ilium of pelvic girdle

Caudal or coccygeal vertebrae Mainly 3 to 4 caudal vertebrae gets fused to form a small triangular bone called coccyx. It is the vestigial tail in humans