Coffee and milk
Diamond and cow
Pen and ink
Mustard oil and coconut oil
Answer is Wrong!
Answer is Right!
The correct answer is D. Mustard oil and coconut oil.
Substitutes are goods or services that can be used in place of each other. For example, coffee and tea are substitutes, as people can drink either one to get their caffeine fix. Diamonds and cows are not substitutes, as they are not used for the same purpose. Pens and ink are not substitutes, as pens can be used with different types of ink.
Mustard oil and coconut oil are both edible oils that can be used in cooking. They have different flavors and textures, but they can be used interchangeably in many recipes. Therefore, they are considered substitutes.