ISQI certification CTFL_Syll_4.0 Exam Dumps

In branch testing, a conditional branch represents a decision point in the software program where the flow of execution can take different paths based on specific conditions. For example, this could be an "if-else" statement, a "switch-case" statement, or loops where different execution paths are taken depending on the evaluated condition. This type of testing ensures that all possible paths and conditions are executed at least once, which helps in identifying any potential defects in different branches of the code​​.

Boundary Value Analysis (BVA)focuses on test cases at the edges of partitions because defects often occur at boundaries. The temperature ranges are:

≤7 (Too cold → W)

[8-21] (Standstill → X)

[22-29] (Ideal → Y)

≥30 (Too hot → Z)

Atwo-point BVAmeans testing both thelower and upper boundary valuesof each partition.

The correct selection{7,8,21,22,29,30}includes:

7 → Boundary of Too Cold (W)

8 → Lower boundary of Standstill (X)

21 → Upper boundary of Standstill (X)

22 → Lower boundary of Ideal (Y)

29 → Upper boundary of Ideal (Y)

30 → Lower boundary of Too Hot (Z)

This ensures maximum boundary coverage.

Statement coverage is a structural coverage metric that measures the percentage of executable statements in the source code that are executed by a test suite1. Decision coverage is another structural coverage metric that measures the percentage of decision outcomes (such as branches or conditions) in the source code that are executed by a test suite1. Decision coverage is a stronger metric than statement coverage, because it requires that every possible outcome of each decision is tested, while statement coverage only requires that every statement is executed at least once2. Therefore, if a test suite achieves 100% decision coverage, it also implies that it achieves 100% statement coverage, because every statement in every branch or condition must have been executed. However, the converse is not true: 100% statement coverage does not guarantee 100% decision coverage, because some branches orconditions may have multiple outcomes that are not tested by the test suite2. For example, consider the following pseudocode:

if (x > 0) then print(“Positive”) else print(“Non-positive”) end if

A test suite that executes this code with x = 1 and x = -1 will achieve 100% statement coverage, because both print statements are executed. However, it will not achieve 100% decision coverage, because the condition x > 0 has only been tested with two outcomes: true and false. The third possible outcome, x = 0, has not been tested by the test suite. Therefore, the test suite may miss a potential bug or error in the condition or the branch.

The other options, such as stale transition coverage, equivalence class coverage, and boundary value coverage, are not guaranteed to be 100% by achieving 100% decision coverage. Stale transition coverage is a structural coverage metric that measures the percentage of transitions between states in a state machine that are executed by a test suite3. Equivalence class coverage is a functional coverage metric that measures the percentage of equivalence classes (or partitions) of input or output values that are tested by a test suite4. Boundary value coverage is another functional coverage metric that measures the percentage of boundary values (or extreme values) of input or output ranges that are tested by a test suite4. These metrics are independent of decision coverage, because they are based on different aspects of the system under test, such as its behavior, functionality, or specification. Therefore, achieving 100% decision coverage does not imply achieving 100% of any of these metrics, and vice versa. References = ISTQB® Certified Tester Foundation Level Syllabus v4.0, Test Coverage in Software Testing - Guru99, Structural Coverage Metrics - MATLAB & Simulink - MathWorks India, Test Design Coverage in Software Testing - GeeksforGeeks.

Comprehensive and Detailed Explanation From Exact Extract:

This question applies theState Transition Testingtechnique.

Let’s evaluateOption Dstep-by-step:

NORMAL MODE → DEGRADED MODE:✅Valid on“FAILURE DETECTED”

DEGRADED MODE → NORMAL MODE:✅Valid on“ALL FAILURES CLEARED”

NORMAL MODE → DIAGNOSTIC MODE:✅Valid on“SELF DIAGNOSTIC INITIATED”

DIAGNOSTIC MODE → DEGRADED MODE:❌Invalid– there isno defined transitionfrom DIAGNOSTIC MODE directly to DEGRADED MODE.

According to the state diagram, DEGRADED MODE can only be entered:

From NORMAL MODE (on FAILURE DETECTED), or

Not from DIAGNOSTIC MODE at all.

This violates the rule:

“State transition testing uses a model where test cases are designed to execute valid and invalid transitions.”

(ISTQB CTFL Syllabus v4.0, Section 4.2.4 – State Transition Testing, Page 40)

Thus, OptionDcontains aninvalid transition, making it the correct answer.