What should be my approach in solving this op amp circuit
There are several things wrong with the diagram for this question.

The fact they define a Vz suggests that those are zener diodes, not ordinary diodes. They should be drawn as zeners.

The fact that the correct answer is +/- 12.2v suggests that the zeners should be drawn in anti-series, so that whichever way the output swings, they will start conducting at 11+1.2 = 12.2V.

What concept are you lacking? The idea that questions can sometimes be wrong. 

It may not be the question setter's hand-drawn sketch that was wrong, it could be the typesetter's unfamiliarity with electronics notation who just 'read' a couple of anti-series zeners as a pair of series diodes (I've had this sort of thing happen a few times to me). But it is a failure of the question setter to proof-read the result. Was this an exam question, or is it an exercise in a published book? Beware the rest of the questions!