The correct answer is: C. Not related with each other.
An indifference curve is a graph showing combinations of two goods that provide the same level of satisfaction to a consumer. The consumer is said to be indifferent between any two points on the curve.
Complementary goods are goods that are used together, such as cars and gasoline. If the price of cars goes up, the demand for gasoline will go down, because people will buy fewer cars.
Substitute goods are goods that can be used in place of each other, such as coffee and tea. If the price of coffee goes up, the demand for tea will go up, because people will switch to drinking tea instead of coffee.
Goods that are not related to each other are goods that are not used together and cannot be used in place of each other. For example, bread and shoes are not related to each other. If the price of bread goes up, the demand for shoes will not be affected.
I hope this helps! Let me know if you have any other questions.