Answer:
Second option is the correct answer.
Explanation:
To know if the given set of numbers can be possible lengths for a right triangle, we will use the Pythagorean theorem that states:

a and b are smaller lengths.
Option first:
6cm, 22.9cm, 20.1cm.

=>

=>

This is not a right triangle.
Option second:
10.5cm, 20.8cm, 23.3cm

=>

=>

This is a right triangle.