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.
One example: Article: Homework can put you in a bad mood , and that might actually be a good thing. Researchers from the University of Plymouth in England doubted whether mood might affect the way kids learn. To find out the answer, they did two experiments with children. The first experiment tested 30 kids. Someshapes were hidden inside a different, larger picture. The kids had to find the small shapes while sitting in a room with either cheerful or sad music playing in the background. To test their mood, the scientists asked the kids to point to one of five faces, from happy to sad. Children who listened to cheerful music tended to point to the smiley faces while the others pointed to the unhappy ones. The researchers found that sad kids took at least a second less to find the small shapes. They also found an average of three or four more shapes. In the second experiment, 61 children watched one of two scenes from a film. One scene was happy, and the other was sad. Just like in the first experiment, kids who saw the sad scene acted better compared to the others. The researchers guessed that feeling down makes people more likely to focus on a problem or difficult situation. Not all scientists agree with them, however. Other studies argued that maybe, that cheerful music in the first experiment distracted kids from finding shapes. While scientists work on finding out the answers, it still might be wise to choose when to do your tasks according to your mood. After eating a delicious ice cream, for example, write an essay. 
 Question: Researchers did experiments on kids in order to find out _ . 
 Options: (A) how they really feel when they are learning (B) whether mood affects their learning ability (C) what methods are easy for kids to learn (D) the relationship between sadness and happiness
Solution is here: B
Explanation: It is clearly mentioned in the article that to the check effect of mood on children is the main purpose of the experiment. So, B is the correct answer.

Now, solve this: Article: DNA left at a crime scene could be used in the future to build up a picture of an offender's face, it was revealed tonight. A first step towards genetic _ has been taken by researchers in the US who link specific DNA markers with face shape. To identify the genes, they focused on known mutations  that cause changes of the face and head. Normal versions of these genes were found to influence individual features. For instance, one gene affected the lips, another the shape and configuration of bones around the eyes, and a third the appearance of the mid-face and skull. In total, 20 genes had "significant effects" on facial appearance. Lead scientist Professor Mark Shriver, from Pennsylvania State University, said: "We use DNA to match to an individual or identify an individual, but you can get so much more from DNA. Currently we can't go from DNA to a face, or from a face to DNA, but it should be possible." The implications are far reaching, raising the possibility of creating a data bank of facial types based on genetic markers. DNA from a crime scene could then be used to produce a rough image of the face of an offender or victim. Such genetic mugshots may be more reliable than computer-generated "e-fits" based on witnesses' recollections. Other uses of the technique might include proving the identity of fathers in paternity cases, or visualising our remote ancestors from fossil DNA. The scientists wrote in the online journal Public Library of Science Genetics: "Such predictive modelling could be forensically useful; for example, DNA left at crime scenes could be tested and faces predicted in order to help to narrow the pool of potential suspects. Further, our methods could be used to predict the facial features of descendants, deceased ancestors, and even extinct human species. In addition, these methods could prove to be useful diagnostic tools." The team developed a model which first established a range of physical face shapes from people of mixed West African and European ancestry from the US, Brazil and Cape Verde. Measurements were taken of thousands of point co-ordinates on grids placed over 3D images of the faces. Statistical methods were then used to determine the relationship between facial differences and the effects of gender, ethnic ancestry and individual gene variants. 
 Question: According to Professor Mark Shriver, we know  _  . 
 Options: (A) they can merely match to an individual or identify an individual (B) there is a possibility of going from DNA to a face (C) DNA could be used to produce a rough image of an offender's face (D) this technology is more reliable than computer-generated "e-fits"
Solution:
B