The figure depicts the life-cycle of a defect using state transition testing. State transition testing is a technique that models how a system transitions from one state to another depending on events or conditions. The figure shows six states (S0 to S5) and seven transitions (T0 to T6). The correct sequence of state transitions that follows the figure is S0->S1->S2->S3->S5->S1->S2->S3. This sequence represents the following scenario:
S0: The defect is not yet detected (initial state).
T0: The defect is detected by testing (event).
S1: The defect is reported and registered (state).
T1: The defect is assigned to a developer for fixing (event).
S2: The defect is being fixed by the developer (state).
T2: The developer fixes the defect and delivers a new version (event).
S3: The defect is verified by testing (state).
T5: The testing fails to confirm that the defect is fixed (event).
S5: The defect is rejected by testing (state).
T6: The defect is reassigned to a developer for fixing (event).
S1: The defect is reported and registered (state).
T1: The defect is assigned to a developer for fixing (event).
S2: The defect is being fixed by the developer (state).
T2: The developer fixes the defect and delivers a new version (event).
S3: The defect is verified by testing (state). The other sequences are incorrect, as they do not follow the transitions shown in the figure. Verified References: [A Study Guide to the ISTQB® Foundation Level 2018 Syllabus - Springer], Chapter 4, page 40-41.