Out of 'X' pairs of ribs in humans, only 'Y' pairs are true ribs. Select the option that correctly represents values of X and Y and provides their explanation :
1
X = 24, Y = 12 True ribs are dorsally attached to vertebral column but are free on ventral side
2
- X = 12, Y = 7 True ribs are attached dorsally to vertebral column and ventrally to the sternum
3
X = 12, Y = 5 True ribs are attached dorsally to vertebral column and sternum on the two ends
4
X = 24, Y = 7 True ribs are dorsally attached to vertebral column but are free on ventral side