Sentence I talks about 'greatest literary works' and sentence II talks about the preference of writers. It can be noted that sentence II is a condition or reason for sentence I. So, the connector/s must indicate the relation between the two sentences.
Accordingly, 'and' (used to introduce an additional comment or interjection) and 'because' (for the reason that; since) are the only connectors that match the context of the given sentences and can thus be used.
But- used to introduce a phrase or clause contrasting with what has already been mentioned
Or- used to link alternatives
Hence, the correct answer is option (d).