Answer:
Rating a favorite movie on a digital streaming site, (Option A is correct)
Explanation:
Rating a favorite movie on a digital streaming site might contribute to recommendations you see online such as on videos streaming site. After viewing the movie, you rate the movie to like or dislike, or rate on five stars. Your this rating might contribute to recommendation for others. If a movie has a very low rating, it means that this movie is not recommended for you than the movie which has the highest rating by people. For example, most probably you like to watch the movie on streaming site that has the highest numbers of likes and views
Other actions might not contribute toward recommendation:
Searching an item using the search engine might not contribute toward the recommendation you see online. Because when you search in a search engine, you may not rate the item you are searching for in it.
Furthermore, purchasing a new t shire from an online retailer may not contribute toward recommendation because you purchased the t-shirt and may not rate it.
All of the above option is only acceptable, when all options allow you to rate online or recommend online. Therefore, only first option allow you to rate your favorite movie on a digital streaming site that might contribute towards recommendation you see online.