Marginalism mean that human have to compare the benefit of the option they select against what they give up (opportunity cost) can someone me come with a example this is economic hw

Marginalism occurs when people decide when people make choices about the value of one more unit of a given item. The best example of this is the diamond-water paradox. Water has more value in nature than diamonds. Water is more widely available than diamonds. So a single unit of diamonds has more value then a single unit of water based on the margins.

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