ISEB-SWTINT1 Question #47: Real Exam Question with Answer & Explanation

Scenario 1 A computerised system is being created to monitor the life support system on board a submarine. It monitors air quality, water supplies and temperature. This system will be supplied and maintained by SubsInc. SubsInc uses the V-model for software development and conducts four levels of testing, from unit through to operational and site acceptance testing. Two key risks identified for the air quality system are: 1. If the percentage of oxygen in the air falls too low, personnel may suffocate 2. If the concentration of carbon dioxide in the air rises too high, the air may become toxic. To address these risks, the requirement specification for this system includes the following requirements: R1) Oxygen must be replaced as it is consumed. R2) Carbon dioxide must be removed from the air. These requirements must be reflected in the functional, technical and program specification documents. You are a newly recruited test manager. Which of the following test design techniques would be most suitable for testing that the oxygen is released at the required times?