Question

question ①
c₁ and c₂ have specific names, which are the

answer
atlas and the axis

sacrum and the coccyx

atlas and the coccyx

cervical and the costal

i dont know yet

Explanation:

In human anatomy, the first cervical vertebra ($C_1$) is called the atlas and the second cervical vertebra ($C_2$) is called the axis. The other options refer to different parts of the spine (sacrum and coccyx are lower - part bones, not $C_1$ and $C_2$; "cervical" is a general term for neck - region vertebrae and "costal" relates to ribs).

Answer:

A. atlas and the axis