The answer is the last one, D. All of the other transitions indicate that the writer will either go into further detail on the subject or list other reasons as to why this would be correct. However, D clearly uses a contrasting transition to introduce a new argument.
d). Movies demand little effort from an audience; on the contrary, audiences often eat, text, and chat during the film.
Explanation:
This is the sentence that uses an appropriate transition to contrast ideas. In these sentences, we see two ideas joined by a transition. However, in order for a transition to be effective, the transition needs to be able to clearly explain how the two ideas connect. The last option is the one that conveys this in the clearest way, as it connects the idea of movies demanding little effort and audiences eating, texting and chatting during the film.
