Answer: A
Step-by-step explanation:
when any 2 sides are added together, they much be larger than the 3rd side
a-
12+ 16 >20
12+20>16
16+20>12
b-
3+4=7 7 is not >7 so not possible
c-
5+6 is 11.. 11 is not greater that 61- not possible
d-
18+18= 36. 36 is not greater than 36- not possible
