Answer:
The correct answer is Fire trucks.
Explanation:
According to the scenario, the given data are as follows:
1. Building blocks buy = $50
Increase in units = 100 units
2. Fire trucks buy = $20
Increase in units = 80 units
( which means in $50 Fire trucks can be bought 2.5× existing units)
So, In $50 Fire trucks increase in unit = 80 units × 2.5 = 200 units
3. Trains buy = $5
Increase in units = 15
( which means in $50 Trains can be bought 10× existing units)
So, In $50 Trains increase in unit = 15 units × 10 = 150 units
Hence, Fire trucks will give the maximum utility.