In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
--------
Question: What does research show about sexual orientation?, Context: Scientists do not know the exact cause of sexual orientation, but they believe that it is caused by a complex interplay of genetic, hormonal, and environmental influences. They favor biologically-based theories, which point to genetic factors, the early uterine environment, both, or the inclusion of genetic and social factors. There is no substantive evidence which suggests parenting or early childhood experiences play a role when it comes to sexual orientation. Research over several decades has demonstrated that sexual orientation ranges along a continuum, from exclusive attraction to the opposite sex to exclusive attraction to the same sex.

Answer: they believe that it is caused by a complex interplay of genetic, hormonal, and environmental influences


Question: Who practices SODIS?, Context: Solar water disinfection (SODIS) involves exposing water-filled plastic polyethylene terephthalate (PET) bottles to sunlight for several hours. Exposure times vary depending on weather and climate from a minimum of six hours to two days during fully overcast conditions. It is recommended by the World Health Organization as a viable method for household water treatment and safe storage. Over two million people in developing countries use this method for their daily drinking water.

Answer: Over two million people


Question: How did the the solution solve issues?, Context: In the 19th century, the city was transformed by development relating to its status as a trading center, as well as by European immigration. The city adopted the Commissioners' Plan of 1811, which expanded the city street grid to encompass all of Manhattan. The 1825 completion of the Erie Canal through central New York connected the Atlantic port to the agricultural markets and commodities of the North American interior via the Hudson River and the Great Lakes. Local politics became dominated by Tammany Hall, a political machine supported by Irish and German immigrants.

Answer:
expanded the city street grid to encompass all of Manhattan