Read the following passage carefully:

Although, India has the second largest urban population in the world and it also has a large size of slum population, till 2001 Census data on slums was not available. The Registrar General of India enumerated slum population in the country for the first time in India in 2001 and that too only for 743 towns and cities. Only 640 towns and cities were reported having any slum out of the total 5161 towns in India in 2001. In 2011 Census, data on slums was collected from 4041 cities and towns and only 2542 reported having any slum and the slum population was only 68 million. Pronab Sen Committee constituted by the Planning Commission in 2010 had estimated slum popultion at 93 million. On the other hand, UNHabitat (2006) put this number at estimated 170 million. 

Answer the following questions on the basis of facts described in the above passage: