Gce Model Questions Vol1 2023 Geography Question 26

A coastal town is exposed to two environmental hazards: flooding and landslides. Historically, flooding occurs on average once every 5 years causing an average damage of \(£12\) million per event, while landslides occur once every 8 years causing an average damage of \(£9\) million per event. Three mitigation options are proposed: A) Flood mitigation only - reduces flood frequency by 40 % (damage per event unchanged) and costs \(£15\) million. B) Landslide mitigation only - reduces landslide damage by 30 % but increases landslide frequency by 20 % and costs \(£10\) million. C) Combined mitigation - applies both A and B together and costs \(£22\) million. Assuming a 20‑year planning horizon, which option yields the lowest expected total cost (expected damage plus project cost)? State the option letter (A, B or C).