A child who cannot sit up by himself at 12 months is: A. Experiencing developmental delays
B. Developing normally
C. Slowly developing but still within the range of normal
D. Developing more quickly than would be expected​

C. Slowly developing but still within the range of normal

Explanation

A. Experiencing developemental delays.

Explanation:

A child should be trying to walk at 12 months, so if they can't even sit up at 12 months, they are developing slower than normal.

i would definitly say b : )