Option A is the best paraphrase. It captures the main idea of the source text by explaining how, in everyday life, our brains are constantly absorbing important information using the attentional system. It then accurately describes the shift that happens when we watch a movie, we let go of that control and allow the film to direct our attention instead. This aligns well with what Millar is saying.
Options B and C do a decent job but miss the mention of the attentional system and the idea of "turning off our tractor beams," which is central to Millar's explanation. Although they're not entirely wrong, they're not as complete as Option A.
Option D introduces inaccuracies by suggesting that movies control our brains in theaters but not at home, which isn't a claim made in the original text.
So, in this case, Option A is the most accurate paraphrase of the source.