Generate an explanation for the given claim using the provided supporting material from the paragraph. Please consider the following points while generating an output. 1) The claim will always have supporting proof in the paragraph, and the paragraph will have a clear point of view supporting the claim. 2) There can be instances where direct correlation to the claim is not available. Make use of the sentences in the paragraph to provide a corresponding output supporting the claim. 3) The explanation should be at least one and at most twelve sentences long.
Q: Paragraph: "In the third and final presidential debate, Republican nominee Donald Trump blamed President Barack Obama and Democratic nominee Hillary Clinton for many of the problems faced by people in New Hampshire. Trump said that included drug addiction. ""The single-biggest problem is heroin that pours across our southern borders, just pouring, and destroying their youth and is poisoning the blood of their youth and plenty of other people,"" Trump said. We've all heard of poppy fields blooming in Afghanistan, but is Trump right that heroin is entering the United States largely through the southern border? Yes. Even though Southwest Asia supplies heroin to most of the rest of the world, nearly all of the heroin available in the United States comes from Mexico and South America. ""Mexico, and to a lesser extent, Colombia, dominate the U.S. heroin market, because of their proximity, established transportation and distribution infrastructure, and ability to satisfy US heroin demand,"" the U.S. Drug Enforcement Administration wrote in its National Drug Threat Assessment of 2015. ""Mexico continues as the primary supplier of heroin to the United States,"" the White House's page on the international heroin market reads. ""Estimated cultivation of opium poppy reached 10,500 hectares in 2012, with an estimated pure potential production of 26 metric tons."" Here's a chart from the DEA report demonstrating the prevalence of heroin from the southern border: As you can see, South America and Mexico have been the sources for much of the heroin in U.S. markets for the past two decades. In recent years, Mexican traffickers have expanded by simultaneously wedging black tar heroin into Northeastern markets dominated by Colombian white powder heroin and increasing production and distribution of white powder heroin themselves. Mexican heroin accounted for 45 percent of the total weight of heroin the DEA seized and analyzed in 2012 (South American heroin accounted for 51 percent). By 2014, the proportion of Mexican heroin had grown to 79 percent (South American heroin made up about 17 percent), DEA spokesman Russell Baer told PolitiFact in September. This market share is also reflected in the amount of heroin seized at the border and the amount grown in Mexico. From 2013 to 2015, the amount of poppy fields cultivated in Mexico increased by 169 percent from 11,000 hectares to 28,000 hectares, according to Baer. In 2008, the total amount of heroin seized at the U.S.-Mexico border (about 560 kilograms) surpassed the amount seized from commercial airlines for the first time (about 400 kilograms). Border seizures nearly quadrupled from 2008 to 2015 (2,210 kilograms), according to data provided to us by Baer. ""The majority of the drugs in the U.S. market are trafficked across the Southwest Border from Mexico into the US. Southwest Border seizures conducted by U.S. Customs and Border Protection, while not the complete picture, provide insight into trafficking trends,"" he said. Traffickers typically smuggle the drugs in through secret compartments in vehicles across the border (illegally and legally), transport them to stash houses in hub cities like Dallas, Los Angeles and Phoenix, and then distribute to the Midwest and East Coast. Our ruling Trump said heroin ""pours across our southern borders."" The vast majority of heroin in the United States comes from Mexico and South America." Claim: Heroin .. pours across our southern borders.
A:
Trump said heroin "pours across our southern borders." The vast majority of heroin in the United States comes from Mexico and South America.