Software Testing and Quality Control

Stress testing determines system stability by pushing it beyond normal operating conditions to identify breaking points. Recovery testing checks recovery after failures, load testing measures response under expected demand, and reliability testing focuses on consistent performance over time.

Compliance testing verifies that a product meets specified standards for efficiency, interoperability, or other defined criteria. Compatibility testing checks if systems work together, interoperability testing ensures data exchange, and performance testing measures speed.

Usability testing involves observing real users interacting with a product to identify errors, usability issues, and improvement opportunities. Soak testing tests for memory leaks over time, scalability testing handles growth, and acceptance testing validates requirements.

Recovery testing verifies a system's ability to recover from crashes, hardware failures, or other catastrophes. Restarting the computer while an application runs and then checking data integrity is a classic recovery test scenario. Load testing measures performance under expected load, not recovery. Performance testing is a broader category that includes load testing. Reliability testing focuses on consistent behavior over time, not recovery from failures.

Stress testing evaluates system stability under extreme, spike, or beyond-limit conditions such as a DoS attack or sudden user spikes. Load testing determines behavior under expected peak loads, while recovery testing measures recovery speed.

Load testing measures system performance under expected user loads. Testing response times at 500, 750, and 1000 users is classic load testing - checking how the system performs at various load levels within expected capacity. Stress testing goes beyond expected load to find breaking points. Performance testing is the broader umbrella category that includes both load and stress testing.

Ergonomics testing (or usability testing) focuses on how well the UI presents information and how easy it is for users to understand and interact with the system. Option B directly addresses whether information is comprehensibly presented, which is core to ergonomics. Option A mentions 'without prototype' which doesn't define what ergonomics tests - it's not about whether a prototype exists, but about the comprehensibility of the interface itself.

Security must be integrated throughout all phases: design, development, and testing. Focusing on only one phase leaves vulnerabilities. Security by design is most effective when applied continuously.

White-box testing (also called glass-box or clear-box testing) involves full knowledge of the application's internal structure, code, and logic, allowing testers to examine paths, conditions, and data flow. Black-box testing treats the application as an opaque system, testing only inputs and expected outputs without seeing internal code. White-box is typically done by developers, while black-box simulates an external attacker or user perspective.

White-box testing involves analyzing the actual source code, byte code, or binary of an application to identify security vulnerabilities, coding errors, and suspicious patterns. Using regular expressions (regex) to scan code for known vulnerability patterns, dangerous function calls, or tainted data flow is a classic white-box static analysis technique. Black-box testing only tests the running application without code access, while grey-box combines both approaches.

Software testing is often legally mandated or required by contracts and specific standards (e.g., safety-critical system regulations). Thus, the statement is correct, making True the right option and False incorrect since testing is frequently obligatory for compliance.

Quality assurance encompasses multiple activities including maintaining development standards, providing training, and conducting defect analysis. All these elements work together to ensure software quality throughout the development lifecycle.

Deciding when to stop testing must balance risk factors (including technical, safety, and business aspects) alongside project constraints (such as time and budget). Since both elements are essential to the decision, choosing only risk or only constraints is incomplete, making 'both 1 and 2' correct.

Debugging is the process of identifying and fixing defects, which is primarily done by developers who write the code. Testing is the process of evaluating software to find defects, which is primarily done by testers who verify the system from a user perspective. This separation of concerns helps maintain objectivity in testing.