A. Individuals or families

B. Enterprise

C. social groups

D. country or government.

Finance, also known as public finance or public economics, is an important branch of economics, the core course of financial specialty in colleges and universities, and an indispensable part of the knowledge structure of financial management talents under the condition of modern market economy. Finance is one of the most challenging disciplines in the field of economics, and it is also a comprehensive discipline integrating economics, politics, public management, law, sociology and other disciplines.

Finance is a discipline to study government financial activities, which mainly includes the following aspects:

1, financial system and financial management: study the government's financial system, financial laws and policies, and the government's functions and roles in financial management.

2. Fiscal revenue: study various sources of government revenue such as taxes and fees, and how to improve the efficiency of fiscal revenue.

3. Financial expenditure: study various government expenditures, including social welfare, education, national defense, public facilities construction, etc. And how to allocate and utilize fiscal expenditure reasonably.

4. Budget: Study the preparation and implementation process of government budget, and how to achieve budget balance and stability.

5. Fiscal policy: study the government's policies to regulate economic and social development through fiscal means, such as fiscal stimulus policy and fiscal contraction policy.

6. Finance and economic development: study the influence and function of finance on economic development, including how to promote economic growth and improve social welfare.