Concept:Tea and coffee are substitute goods, so their demand is competitive demand.
Explanation:When two goods can replace each other, their demand is called competitive demand.
A consumer can choose to buy either tea or coffee instead of buying both together.
Therefore, a change in the price of one affects the demand for the other.
For example, if the price of tea rises, consumers may switch to coffee, increasing the demand for coffee.
This shows that tea and coffee compete in the market as substitutes.
Answer:B. competitive