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: Many people say dolphins are very intelligent. They seem to be able think, understand, and learn things quickly. But they are smart like humans or more like cats or dogs? Dolphins use their brains differently from people. But scientists say dolphin intelligence and human intelligence are alike in some ways. How? FACT 1: Talk to Me Like humans, every dolphin has its own "name". The name is a special whistle . Each dolphin chooses a specific whistle for itself, usually by its first birthday. Actually, scientists think dolphins, like people, "talk" to each other about a lot of things, such as their age, their feelings, or finding food. And, like humans dolphins use a system of sounds and body language to communicate. But understanding their conversations is not easy for humans. No one "speaks dolphin" yet, but some scientists are trying to learn. FACT 2: Let's Play Dolphins are also social animals. They live in groups called pods, and they often join others from different pods to play games and have fun ---just like people. In fact, playing together is something only intelligent animals do. FACT 3: Fishermen's Helpers Dolphins and humans are similar in another way: both make plans to get something they want. In the sea of southern Brazil, for example, dolphins use a interesting strategy to get food. When fish are near a boat, dolphins signal to the fishermen to put their nets in the water. Using this method, the men can catch a lot of fish. What is the advantage for the dolphins? Why do they assist the men? The dolphins get to eat some of the fish.
Question: What is the text mainly about?
Options: (A) The comparison between dolphins and humans. (B) The relationship between dolphins and humans. (C) Different types of dolphins. (D) The habitual behavior of dolphins.

Ex Output:
A

Ex Input:
Article: Long long ago, there was a man who was good at shooting arrows.He asked the king to declare him as the greatest archer of the country.The king was about to do so when an old servant of the king said,"Wait,sir.I know an old man who lives in the forest.He is a much greater archer.Let this young man go to him and learn from him for at least three years." The man could not believe what the servant said,but he went and found the old man and he was! For three years he learned from him.Then one day,when he thought he had learned everything,the thought arose in him:"If I kill this old man,then I will be the greatest archer." The old man had gone to cut wood and he was coming back carrying wood on his shoulder.The young man hid behind a tree,waiting to kill him.He shot an arrow.The old man took a small piece of wood and threw it.It struck the arrow and the arrow turned back and wounded the young man very deeply.The old man came,took out the arrow and said. "I knew that some day or other you were going to do this.That's why I have not taught you this secret.There is no need to kill me.My Master is still alive,and I'm nothing before him.You must be with him for at least thirty years.And he is very old,so go fast! Find the old man!"
Question: The young archer wanted to kill the old man because _ .
Options: (A) he could then become the greatest archer (B) he had nothing more to learn from him (C) the old man refused to teach him everything (D) the king's old servant ordered him to do SO

Ex Output:
A

Ex Input:
Article: _ , or housewives, who have crowded into gold stores across China, buying up 300 tons of gold over the past two weeks. No wonder gold prices have steadied after taking a dive. During the May Day holiday, gold stores were crowded with mostly female customers. Most of them are middle-aged "Chinese housewives". This group of buyers has risen to fame recently. They are big spenders and are desperate to get their hands on a bargain. "I bought some gold jewellery and kept them as a gift for my son when he gets married," said a buyer from Shanghai. The gold business is skyrocketing. "Our sales are growing by the day. Yesterday we sold more than ten million yuan of gold products," a gold store salesperson said. The gold rush in China started about two weeks ago thanks to a decline in global gold prices. Media reports suggest that Chinese housewives have spent about 100 billion yuan, or about 16 billion US dollars, purchasing 300 tons of gold since mid-April. That has helped support gold prices. "Gold prices depressed since the middle of last month but have risen gradually. That is mainly due to the strong demand from Asian markets," said foreign trader Zhang Chen from Industrial & Commercial Bank of China. "Some people even joked that Chinese housewives have beaten Wall Street analysts." For Chinese people, with limited investment options, the only thing better than buying gold is buying gold at discount prices.
Question: The whole passage mainly developed _ ?
Options: (A) by comparison (B) by contrast (C) by quotation (D) by time order

Ex Output:
C