By Alexei Oreskovic SAN FRANCISCO (Reuters) – Facebook Inc wants its users in India to hang up on advertisers. The Internet social networking company is testing a new type of ad in the country that allows mobile phone users to click a button that calls a brand advertiser, immediately hangs up and then receives a return call. The so-called “missed call” ad was specially created by Facebook to appeal to users in the world’s second-most populous country, and potentially in other emerging markets. Facebook has more than 100 million users in India, with the majority accessing the service on so-called feature phones, which lack touchscreens and other capabilities of higher-end smartphones.