ISTQB CTAL-TTA Exam - Topic 4 Question 44 Discussion

Actual exam question for ISTQB's CTAL-TTA exam

Question #: 44
Topic #: 4

BestFor Incorporated is a rapidly growing online financial services company that offers guidance to its customers on a range of financial products. Its first website, BestForMortgages, was launched two years ago, shortly followed by BestForPensions. The popularity of both sites has driven the company to expand its offerings into other sectors and a third website, BestForFood, has recently been released.

The first two websites have proven to be functionally robust but suffered from performance issues due to:

Underestimation of concurrent user access at peak times in its original operational profiles

Data volumes rapidly growing beyond expectations on a single database shared by both sites.

All three websites share the same web server.

The BestForFood system has been running live for several months, however the following significant non-functional defects have been recorded:

A) The layout and navigation of the BestForFood website was not considered by the users as consistent with BestForPensions and BestForMortgages

B) Soon after delivering the BestForFood system the performance of both BestForPensions and BestForMortgages noticeably slowed

C) The time taken to diagnose, repair and re-test production defects did not meet BestForFood service level agreements

D) BestForFood performance was adversely impacted by unexpected growth in data volumes

E) The time taken to install monthly builds into the production system exceeded agreed timescales.

Which TWO of these defects might have been prevented had portability testing and compatibility testing been employed?

Aa and b

Bc and e

Cb and c

Da and d

Show Suggested Answer

Suggested Answer: A

Analysis:

The significant non-functional defects recorded for the BestForFood system indicate issues that could be mitigated by appropriate non-functional testing strategies:

Portability Testing:

Ensures that the application can operate in different environments without issues. This could have addressed the defect related to the layout and navigation consistency across different websites (Defect A).

Compatibility Testing:

Ensures that the application works well with other systems and environments. This could have helped in preventing the performance issues noticed in the BestForPensions and BestForMortgages websites after the deployment of BestForFood (Defect B).

Explanation of Incorrect Options:

C . The time taken to diagnose, repair and re-test production defects: This is more related to maintainability and operational processes.

D . BestForFood performance impacted by data growth: This is better addressed through performance and scalability testing.

E . Installation time exceeding agreed timescales: This is related to deployment and operational efficiency.

The ISTQB CTAL-TTA syllabus and standard non-functional testing practices emphasize the importance of portability and compatibility testing for ensuring smooth operation across different environments and systems.

Sources:

ISTQB-CTAL-TTA Syllabus

General knowledge on non-functional testing practices.

by Gregoria at Jan 05, 2026, 05:16 AM

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2 months ago

I think the key here is to focus on the non-functional defects that relate to compatibility and portability. Defects A and B seem to be about consistency and performance across the different websites, so those could have been caught through compatibility testing.

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