Final answer:
Operational assets (d) are the equipment and devices that aid in the production and delivery of goods and services, which are part of physical capital and directly contribute to labor productivity by increasing the quantity or quality of physical capital.
Step-by-step explanation:
The equipment and devices that perform a variety of tasks in the creation and delivery of goods and services are referred to as Operational assets option d. These are a component of physical capital and can include a wide range of items used by firms and also cover infrastructure such as roads and rail systems. Operational assets are essential for a business's everyday operations and are directly involved in the production process. Investment in these assets can lead to an increase in labor productivity by either adding to the quantity of physical capital or improving its quality, which in turn can result in higher productivity in the future.