Read the following passage and answer questions .

"The Calendar", argued Meghnad Saha, the distinguished scientist and the leader of calendar reform in India, "is an indispensable requisite of modern civilised life." He could have gone further than that, The need for a calendar has been strongly felt - and well understood -well before the modern age. The calendar, in one form or another, has been an indispensable requisite of civilised life for a very long time indeed. This explains why so many calendars are so very old, and also why most civilisations, historically, have given birth to one or more specific calendars of their own. The multiplicity of calendars within a country and within a culture (broadly defined) has tended to relate to the disparate preoccupations and concerns of different groups that co-exist in a country. The study of calendars and their history, usage and social associations can provide a fruitful understanding of important aspects of a country and its cultures. For example, since calendars often have religious roles, there is sometimes a clear connection between regional, religious and domestic calendars. Indeed, even the global calendars of the world are often classified as 'Christian', 'Muslim', 'Buddhist' , and so on. The connection between calendars and cultures, however, goes well beyond this elementary linkage. Since the construction of calendars requires the use of mathematics as well as astronomy, and since the functioning and utilisation of calendars involves cultural sophistication and urbanity, the history of calendrical progress can tell us a lot about the society in which these developments occur.