Answer:
The correct answer here is D) which has many perfect substitutes.
Step-by-step explanation:
A product is a standardize product regardless of which firm has furnished the product, the consumers will regard these furnished products as identical no matter which firm has made it, because they are only concerned with the size and quality of the product, so we can say that standardize products are perfect substitutes and there are many commodities in the market which are standardize products like grains, milk, curd etc.