The correct option is D either ; or
Correlative conjunctions are pairs of conjunctions that work together. Some examples are either/or, neither/nor, and not only/but also. The given sentence requires the use of a correlative conjunction. The combination either/or indicates that there is a choice between the two choices, and only one can be selected. Either is always used with or and it is used to express alternatives and or a choice between two (and sometimes more) things. Thus Option D is correct. The combination neither/nor indicates that neither of the two choices can be selected. In other words, neither choice is available. Thus Option A is incorrect as neither/nor - When they're paired up they negate both parts of a statement while it is inferred in the sentence that the speaker has to decide between reading a novel or going out with his friends. We use as soon as to show that something happens immediately, i.e. ‘at the very moment another action is completed’,.'.And' helps to add one clause or phrase to another similar one. Option B is incorrect as the two clauses are not of the similar nature.'.'But' is used to introduce a word or phrase that contrasts with what was said before.' and ' also' indicates' in addition'.Thus Option C can be discarded.