Please help urgent!

Based on this table that lists the advantages and disadvantages of dam-and-reservoir systems, name one advantage, and one disadvantage that is most important. Explain why you think each of those is most important. Answer in complete sentences and make sure you include one advantage and one disadvantage.

Advantages
Provides irrigation water above and below the dam
Provides water for drinking
Reservoir useful for recreation and fishing
Can produce cheap electricity (hydropower)
Reduces downstream flooding of cities and farms

Disadvantages
Flooded land destroys forests or cropland and displaces people
Large losses of water through evaporation
Deprives downstream cropland and estuaries of nutrient-rich salt
Risk of failure and devastating downstream flooding
Disrupts migration and spawning of some fish