The limiting reagent in this situation is the bread.
In this situation, the limiting reagent is the ingredient that will be completely used up and will limit the number of sandwiches that can be made. To determine the limiting reagent, we need to compare the amount of each ingredient with the amount required to make one sandwich.
Given that each sandwich requires 2 pieces of bread, 1 piece of cheese, and 1 piece of ham, we can find the limiting reagent by dividing the available amount of each ingredient by the requirement for one sandwich:
Number of sandwiches that can be made with the available ingredients:
Bread: 24/2 = 12 sandwiches
Cheese: 16/1 = 16 sandwiches
Ham: 20/1 = 20 sandwiches
Since the number of sandwiches that can be made using the bread is less than the number that can be made using the cheese or ham, the limiting reagent in this situation is the bread.