Concept:The Union Budget is a detailed annual statement of the government's planned revenue and expenditure.Explanation:The budget is prepared for the Indian financial year. This financial year runs from April 1 to March 31 of the following year. The Finance Minister presents the budget on February 1 each year. This gives Parliament time to approve it before April 1. The April–March cycle matches India's tax assessment and accounting periods. It has been used since British times for consistency. The other options are incorrect. The calendar year (Jan–Dec) is not used. A fiscal year from Jan to Dec is followed by the USA but not India. The July to June period was used before 1867 but was changed to the current system.Answer:C. Financial year from April to March