Suppose Chad decides to bake lemon muffins. Which result would be a cost?

 - Chad will give up the chance to eat cornbread muffins. He thinks cornbread muffins are tastier than lemon muffins.
 - Chad will get to eat more muffins. He can make more lemon muffins than cornbread muffins.
This result is a cost. It involves giving up or spending something that Chad wants or needs:
Chad will give up the chance to eat cornbread muffins. He thinks cornbread muffins are tastier than lemon muffins.