which have sex ratios of 108 and above are usually presumed as engaging in sex selection. However, deviations in sex ratios at birth can occur for natural causes too. Nevertheless, the practice of bias against girls, through sex selective abortion, female infanticide, female abandonment, as well as favouring sons with regard to allocating of family resources is well documented in parts of South Asia, East Asia, and the Caucasus. Such practices are a major concern in China, India and Pakistan. In these cultures, the low status of women creates a bias against females. China and India have a very strong son preference. In China, the one child policy was largely responsible for an unbalanced sex ratio. Sex-selective abortion, as well as rejection of girl children is common. The Dying Rooms is a 1995 television documentary film about Chinese state orphanages, which documented how parents abandoned their newborn girls into orphanages, where the staff would leave the children in rooms to die of thirst, or starvation. In India, the practice of dowry is partly responsible for a strong son preference. Another manifestation of son preference is the violence inflicted against mothers who give birth to girls. In India, by 2011, there were 91 girls younger than 6 for every 100 boys. Its 2011 census showed that the ratio of girls to boys under the age of 6 years old has dropped even during the past decade, from 927 girls for every 1000 boys in 2001 to 918 girls for every 1000 boys in 2011. In China, scholars report 794 baby girls for every 1000 baby boys in rural regions. In Azerbaijan, last 20 years of birth data suggests 862 girls were born for every 1000 boys, on average every year. Steven Mosher, president of the Population Research Institute in Washington, D.C. has said: "Twenty-five million men in China currently can't find brides because there is a shortage of women [...] young men emigrate overseas to find brides." The gender imbalance in these regions is also blamed for spurring growth in the commercial sex trade; the UN's 2005 report states that up to 800,000 people being trafficked across borders each year, and as many as 80 percent are women and girls. Biology Embryos that inherit two X chromosomes (XX), one from each parent, are generally identified as girls when born. About one in a thousand girls have a 47,XXX karyotype, and one