Which of the following possibilities will form a triangle?

Side = 15 cm, side = 6 cm, side = 8 cm
Side = 15 cm, side = 6 cm, side = 9 cm
Side = 16 cm, side = 9 cm, side = 6 cm
Side = 16 cm, side = 9 cm, side = 8 cm

The only set of side lengths that can form a triangle is:

Side = 15 cm, side = 6 cm, side = 9 cm

This is because the sum of the lengths of any two sides of a triangle must be greater than the length of the third side. For example, in the first set of side lengths, 15 + 6 = 21, which is greater than 8, so a triangle cannot be formed. The same logic applies to the third and fourth sets of side lengths.