Option 4 is the right answer. The sentence is a suggestion which can be a positive or a negative one. Such sentences are usually in the present tense. Option 1 and 3 use the past tense ('had') and the phrases are grammatically incorrect. Option 2 indicates an obligation/ expectation : For example, should have been on time. Option 4 is the short form of 'should not have', which is grammatically correct Correct sentence : He shouldn't have done it.