If the January publication consists exclusively of articles by Arshad and Behroz, then the April publication can consist exclusively of articles by which of the following groups of authors?

Explanation: এই puzzle টির condition গুলো হল: 1. প্রত্যেকটি magazine এ কমপক্ষে 2-টি articles থাকতে হবে। 2. Rashed ও Sakib এর articles একই magazine এ published হতে পারবেনা। 3. কোন magazine এ Arshad এর article published হলে Behroz এর article ও published হতে হবে। 4. কোন magazine এ Emon এর article published হলে Rashed এর article তার immediate আগের magazine এ published হতে হবে। 5. কোন author এর article পরপর দুটি magazine এ বা একই magazine এ দুবার published হতে পারবেনা। January publication is \(\{A, B\}\). Since A and B are in January, they cannot be in April (Rule 5). Emon cannot be in April since Rashed is not in January (Rule 4). So, April cannot be \(\{E, S\}\) or \(\{E, F\}\). Therefore, the April publication must contain Rashed (for Emon to be in August, if Emon is to publish at all - which he must, according to question premise). Since Rashed is in April, Sakib cannot be in April (Rule 2). The remaining authors who can be in April are D, F, R. April must have at least 2 articles. Only \(\{D, R\}\) satisfies all current constraints (and Rashed is necessary for Emon to publish later). Thus, the correct group is \(\{D, R\}\).