Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

Example Input: Context: Mahjong, that favorite pastime of "old folks" in Shanghai, is finding a new audience among younger players, and many university students are becoming mad about this traditional Chinese game. Students at Fudan University have even formed a Mahjong club. This resurgence of the game, however, is not without its critics. Some people still associate the game with gambling and for many years Mahjong was banned in China. One critic, surnamed Meng, was quoted as saying, "Mahjong is a bad custom that will distract students from studies." But Yu Guangyuan, former vice-president of the Chinese Academy of Social Sciences , says Mahjong is a "healthy, scientific, friendly mind game." Mr. Yu's opinion seems to be shared by the majority of Chinese. They see the game as an activity that requires great concentration and intellectual skill. They also see the game as an important part of Chinese culture and a pastime that brings family and friends closer together. This Spring Festival many families will no doubt spend hours around the Mahjong table getting reacquainted with each other. For them, playing Mahjong is a way of spending quality family time. No one knows who invented Mahjong. Some say it was Confucius, others say the current form of the game was developed right here in Shanghai in the late19th century. It is certainly because of Shanghai that the game enjoys its worldwide popularity. It was brought to America in the 1920s and has since spread throughout Europe and other parts of Asia. There is now a World Championship of Mahjong which is held every year. This year's championship was held in Chongqing and attracted players from America, Europe and Russia, as well as students from Peking University, Tshinghua University and Nankai University. There was no prize money, but the players delighted in using their wits and their understanding of statistics and probability theory to defeat their clever opponents. Of course, Mahjong doesn't have to always be that intense. For young people it can be a way to relax and to socialize, a chance to get away from their computers and talk to other people face to face. So, this Spring Festival, why not get out the "old folks" tiles: it's good to be mad about Mahjong! 
 Question: What is the best title of the passage?
Example Output: mad about mahjong

Example Input: Context: What determines if a baby is a male or female? Recall that you have 23 pairs of chromosomesand one of those pairs is the sex chromosomes. Everyone has two sex chromosomes. Your sex chromosomes can be X or Y. Females have two X chromosomes (XX), while males have one X chromosome and one Y chromosome (XY). If a baby inherits an X chromosome from the father and an X chromosome from the mother, what will be the childs sex? The baby will have two X chromosomes, so it will be female. If the fathers sperm carries the Y chromosome, the child will be male. Notice that a mother can only pass on an X chromosome, so the sex of the baby is determined by the father. The father has a 50 percent chance of passing on the Y or X chromosome, so there is a 50 percent chance that a child will be male, and there is a 50 percent chance a child will be female. This 50:50 chance occurs for each baby. A couples first five children could all be boys. The sixth child still has a 50:50 chance of being a girl. One special pattern of inheritance that doesnt fit Mendels rules is sex-linked inheritance, referring to the inher- itance of traits that are located on genes on the sex chromosomes. Since males and females do not have the same sex chromosomes, there will be differences between the sexes in how these sex-linked traitstraits linked to genes located on the sex chromosomesare expressed. Sex-linked traits usually refer to traits due to genes on the X chromosome. One example of a sex-linked trait is red-green colorblindness. People with this type of colorblindness cannot tell the difference between red and green. They often see these colors as shades of brown ( Figure 1.1). Boys are much more likely to be colorblind than girls ( Table 1.1). This is because colorblindness is a sex-linked, recessive trait. Boys only have one X chromosome, so if that chromosome carries the gene for colorblindness, they will be colorblind. As girls have two X chromosomes, a girl can have one X chromosome with the colorblind gene and one X chromosome with a normal gene for color vision. Since colorblindness is recessive, the dominant normal gene will mask the recessive colorblind gene. Females with one colorblindness allele and one normal allele are referred to as carriers. They carry the allele but do not express it. How would a female become colorblind? She would have to inherit two genes for colorblindness, which is very unlikely. Many sex-linked traits are inherited in a recessive manner. Xc Xc X (carrier female) Xc Y (colorblind male) X Y X XX (normal female) XY (normal male) According to this Punnett square ( Table 1.1), the son of a woman who carries the colorblindness trait and a male with normal vision has a 50% chance of being colorblind. 
 Question: most sex-linked genes are ___________.
Example Output: recessive

Example Input: Context: ZFHX1B encodes Smad-interacting protein 1, a transcriptional corepressor involved in the transforming growth factors beta (TGFbeta) signaling pathway. ZFHX1B mutations cause a complex developmental phenotype characterized by severe mental retardation (MR) and multiple congenital defects. We compared the distribution of ZFHX1B transcripts during mouse and human embryogenesis as well as in adult mice and humans. This showed that this gene is strongly transcribed at an early stage in the developing peripheral and central nervous systems of both mice and humans, in all neuronal regions of the brains of 25-week human fetuses and adult mice, and at varying levels in numerous nonneural tissues. Northern blot analysis suggested that ZFHX1B undergoes tissue-specific alternative splicing in both species. These results strongly suggest that ZFHX1B determines the transcriptional levels of target genes in various tissues through the combinatorial interactions of its isoforms with different Smad proteins. Thus, as well as causing neural defects, ZFHX1B mutations may also cause other malformations. 
 Question: Which gene is responsible for the development of the Mowat-Wilson syndrome?
Example Output:
zeb2