Primary industries are those that involve the extraction or harvesting of natural resources from the environment. These industries are considered the foundation of the economy as they provide raw materials for other industries. Out of the options given, agriculture is an example of a primary industry.

Agriculture:

Agriculture is the cultivation of crops, raising livestock, and the production of plants and animals for food, fiber, medicinal plants, and other products used to sustain and enhance human life. It involves various activities such as planting, growing, and harvesting crops, raising animals for meat, milk, or eggs, and cultivating plants for their medicinal or ornamental value. Agriculture is a primary industry because it directly involves the extraction of resources from the earth and is essential for human survival.

Key Points:
1. Agriculture involves the cultivation of crops and raising livestock for food, fiber, and other products.
2. It includes activities like planting, growing, and harvesting crops, as well as raising animals.
3. Agriculture is a primary industry because it directly extracts resources from the environment.
4. It is essential for human survival and provides the foundation for other industries.

Other options:

a) Automobile manufacturing: This is an example of a secondary industry. It involves the transformation of raw materials (such as steel, rubber, and plastic) into finished products (cars) through various manufacturing processes.

b) Software development: This is an example of a tertiary industry. It involves the creation, design, and development of software and computer applications.

d) Banking: This is an example of a service industry. It involves providing financial services such as lending, borrowing, and investment management. While banking plays a crucial role in the economy, it does not directly involve the extraction of natural resources.

In conclusion, agriculture is an example of a primary industry as it involves the extraction of resources from the environment and is essential for human survival.