is it better to have error control at level 2 or level 4 in OSI Reference model and why?

Answer 1

at the lower layers you are just interested in getting the information transported. It is the responsibility of the upper layers to determine the validity of the data.

Look at it this way, when you drive from point A to point B, do you really care if there are bumps in the road? No, because you just want to get there. Leave it up to the shocks to smooth everything out.

later...