20 POINTS PLUS BRAINLIEST!! PLEASE HELP!

Write the first 4 terms of the sequence if a(4)=36 and a(n)=1/2a(n-1)+12.

A.
36, 30, 27, 25.5
B.
120, 72, 48, 36
C.
456, 216, 96, 36
D.
36, 48, 72, 120