Which example best demonstrates the concept of an economic trade-off? Congress directs additional federal funds to improve highways and expand military facilities after tax revenues increase enough to support both priorities. Congress directs a committee to study highway and military funding before deciding how future federal budget priorities should be adjusted. Congress directs limited federal funds to improve highways instead of expanding military facilities because the budget cannot fully support both priorities. Congress directs existing federal funds to continue supporting highways and military facilities at their current funding levels for another year.