The correct option is B Used
Modal verbs help determine the mood of a sentence, to indicate
obligation, permission, possibility and so on. Semi/quasi modals are
generally modal phrases performing the same function as modals, they
form phrases with 'to', like ought to, need to, used to and so on. 'Used to' refers to a discontinued habit or past situation, when placed here it refers to a game that the speaker loved when he was a child. Hence it's the most suitable option and D is correct. 'Ought' refers to a moral obligation or duty, 'must' refers to an obligation or compulsion and 'need' refers to a necessity or requirement. None of these modals are relevant to the given statement, because it mentions a past situation, hence options A, B and C are incorrect.