Step 1: Understanding physical capital stock.
Physical capital stock refers to the human-made assets that are used in the production of goods and services, such as machines, buildings, and infrastructure (roads). These assets help in increasing the productive capacity of an economy.
Step 2: Analyzing the options.
(A) Machine: Machines are physical capital because they are used in the production of other goods and services.
(B) Buildings: Buildings are also part of physical capital stock, as they are used for production purposes or for housing business activities.
(C) Roads: Roads are part of the physical infrastructure and hence considered physical capital stock.
(D) Fruits: Fruits are not physical capital; they are consumable goods and do not serve as productive assets in the economy.
Step 3: Conclusion.
The correct answer is (D) Fruits, as fruits are not considered physical capital stock.