Answer:
25% probability,
as shown....the method the teacher in the video has used is using the punnet square,
and this question is a mono-hybrid cross type question, hence it is easier,
every mono-hybrid cross by the punnet square will give the following ratio,
=> dominant(homogeneous) : dominant(heterogeneous) : recessive
in this case,
=> normal (homogeneous pair) : normal (heterogeneous pair) : color-blind (homogeneous pair)
=> 1:2:1
which would be out of four possibilities, there is only one possibility of the child born to be color-blind