In this task, you're given an article, a question which often contains a blank and four options (associated with "A", "B", "C", "D"). Your task is to find the correct answer (from the given options) for the question from the given article and return one of the options from "A", "B", "C", and "D". Do not generate anything else apart from one of the following characters: "A", "B", "C", "D". There is only one correct answer for each question.

Ex Input:
Article: Humans aren't the only ones getting a buzz from coffee.Caffeine can improve memory among honeybees and lead to better pollination .According to a recent study published in the journal Science. The study was conducted by a team of researchers at Newcastle University in the United Kingdom.They found that the nectar of some flowers,such as those from grapefruit and lemon plants,as well as certain coffee flowers,contains low doses of caffeine.To get bees to feed on these flowers,the team trained the insects to associate food with the smell of the flowers.They also trained another group of bees to feed on nectar from flowers that were sweetened with a sugar, but did not contain caffeine.After 24 hours,the bees trained on caffeinated flowers returned to these plants three times as often as those trained on the sweetened flowers returned to the uncaffeinated plants. Professor Geraldine Wright led the researchers."Remembering floral traits is difficult for bees to perform at a fast pace as they fly from flower to flower and we found that caffeine helps the bee remember where the flowers are,"Wright said in a statement. Improved memory led to the better pollination.That's because once bees sip the caffeine nectar, they continue to look for more coffee plants to pollinate.This also suggests that caffeine plays a role in improving the bees'ability to search for food. Researchers found that caffeine's effect on the bee brain is similar to its effect on mammals."The change is similar to that produced by caffeine in neurons associated with learning and memory in the rat brain,"Wright said. Bee populations have declining since 2007.The dramatic drop in the insects'numbers has serious effects for ecosystems and the farming industry.Bees are needed in the reproduction of crops and spreading wild flower species.Understanding what keeps bees buzzing could help to make sure that the insects are able to remember and pollinate their favorite flowers.
Question: Which of the following is mentioned in the passage?
Options: (A) Caffeine has no effect on the rat brain. (B) Bee population has been increasing. (C) The nectar of lemon plants contains caffeine. (D) Bees dislike nectar from sweetened flowers.

Ex Output:
C

Ex Input:
Article: All things change except barbers, the ways of barbers, and the surroundings of barbers. These never change. What one experiences in a barber's shop the first time he enters one is what he always experiences in barbers' shops afterward till the end of his days. I got shaved this morning as usual. A man approached the door from Jones Street as I approached it from Main--a thing that always happens. I hurried up, but it was of no use; he entered the door one little step ahead of me, and I followed in and saw him take the only empty chair, the one headed by the best barber. It always happens so. I sat down, hoping that I might sit in the chair belonging to the better of the remaining two barbers, for he was a bit ahead. I watched the probabilities with strong interest. When I saw that No. 2 was gaining on No. 1, my interest grew to solicitude . When No. 1 was gradually losing the race, my solicitude rose to anxiety. When No. 1 caught up again, and both were about to finish and say "Next!" first, my very breath stood still with the _ . But when I saw that he had lost the race by a single instant, I rose angrily and quitted the shop, to keep from falling into the hands of No. 2; for I have none of that firmness that enables a man to look calmly into the eyes of a waiting barber and tell him he will wait for his fellow-barber's chair. I stayed out fifteen minutes, and then went back, hoping for better luck. Unfortunately, all the chairs were occupied now, and four men sat waiting, silent, and looking bored, as men always do who are waiting their turn in a barber's shop. I sat down and waited. At last my turn came. A voice said "Next!" and I give in to No. 2, of course. It always happens so. I smiled and said that I was in a hurry, and it affected him as strongly as if he had never heard it. He explored my hair with his claws and suggested that it needed trimming . I said I did not want it trimmed. He explored again and said it was pretty long for the present style. I said I had had it cut only a week before. He stopped for a moment, and then asked "who cut it?" I stared at him from the mirror and replied "You did!". Then a dog-fight attracted his attention, and he ran to the window and stayed and watched it...
Question: The author left the barber's shop mainly because _ .
Options: (A) he would like to wait for "No. 1" outside (B) he would rather be served by the best barber (C) he lacked the courage to tell "No. 2" his intention (D) he was angry at the slow speed of "No. 1"

Ex Output:
C

Ex Input:
Article: One night there was a woman at the airport who had to wait for several hours before getting her next flight. While waiting, she bought a book and a pack of biscuits to spend the time. She looked for a place to sit and waited. She was reading her book, when suddenly she realized that there was a young man sitting next to her who was stretching his hand, and grabbing the pack of cookies lying between them. He started to eat them one by one. Not wanting to make a fuss about it ,she decided to ignore him. The woman ate the biscuits and watched the clock, while the young thief was also eating them. The woman started to think, "If I weren't such a good and educated person, I would have hit this man by now." Every time she ate a biscuit, he had one, too. The dialogue between their eyes continued and when only one biscuit was left, she wondered what he was going to do. Softly and with a nervous smile, the young man grabbed the last biscuit and broke it into two. He offered one half to the woman while he ate the other half. Briskly she took the biscuit and thought, "What a bad man! How uneducated! He didn't even thank me!" She had never met anybody who made her so angry, and was pleased when her flight was ready. She grabbed her bags and went towards the gate not looking back to where that thief was seated. After getting on the plane and being seated, she looked for her book which was almost finished by now. While looking into her bag she was totally surprised to find her pack of biscuits. "If my biscuits are here," she thought, feeling bad, "those others were his and he tried to share them with me."Too late to say sorry to the young man, she realized with pain, that it was her who had been an uneducated thief, but not him.
Question: According to the passage, the woman bought the biscuits _ .
Options: (A) because she was hungry then. (B) Because the biscuits were on sale. (C) because she wanted to kill time (D) because the young man wanted to eat it

Ex Output:
C