A government is weighing whether to upgrade the rail network and select one of four high-speed routes. The benefits and costs for each route (private benefits, external benefits, private costs, external costs in $bn) are as follows: A: 14,20,0.4,0.1; B: 16,22,1.6,0.4; C: 18,12,0.2,1; D: 20,18,2,4. Which route ought to be selected?
- ARoute A
- BRoute B
- CRoute C
- DRoute D