Question

Opportunity cost is the least desirable alternative given up as a result of a decision.

Answer 1

I guess your question is: is this a true statement?

and the answer is: no, this is not a true statement, it's false.

Opportunity cost is the most desirable alternative. For example if you can earn 100, 50 and 30 dollars, and you choose 100, then your opportunity cost is the 50 dollars you rejected