A cost is O something that is gained when a decision is made
O something that is given up when a decision is made
Oa rational decision
Oa type of benefit

something that is given up when a decision is made

Explanation:

if something costs you it goes away

for example if the cost of some was 2 dollars you would lose two dollars

increases in demand are shown by a shift to the right in the demand curve. this could be caused by a number of factors, including a rise in income, a rise in the price of a substitute or a fall in the price of a complement.

which the answer is:

b