Gce Model Questions Vol1 2025 Computer Studies Question 1

Company X has identified three security threats with the following likelihoods (per year) and monetary impacts: - Threat A: likelihood \(0.03\), impact ₦4,000,000 - Threat B: likelihood \(0.04\), impact ₦2,500,000 - Threat C: likelihood \(0.02\), impact ₦6,000,000 Risk is calculated as \( \text{Risk} = \text{Likelihood} \times \text{Impact} \). Three possible controls are available: - Control X reduces likelihood by 40 % (i.e., multiplies likelihood by 0.6) and costs ₦500,000. - Control Y reduces impact by 30 % (i.e., multiplies impact by 0.7) and costs ₦300,000. - Control Z reduces both likelihood and impact by 20 % (multiplies each by 0.8) and costs ₦600,000. The acceptable residual risk threshold is ₦80,000. Which control should be implemented to bring the highest‑risk threat's residual risk below the threshold at the lowest cost? State the control name.