The correct option is A I know that he has chosen a special place for dinner.
Sentences can be combined using a noun clause, an adverb clause or an adjective clause. From the options, B contains a that-clause ("that he has chosen a special place for dinner"), which is a noun clause that acts as an object . Hence option B is correct. Option A does not use a noun clause subordinator, it uses a coordinating conjunction 'and', hence it is incorrect. Option C has a jumbled set of words: "I know it for dinner". The sentence isn't complete in meaning, hence C is incorrect. Option D is incorrect because '"it" is not required anymore. When the sentence wasn't connected, 'it' was used as a determiner to refer to the previous sentence. After combining them, "that" is used as a relative pronoun that relates the clause to the rest of the sentence, hence D is incorrect.