A/B Testing

Correct Answer: Construct validity threat due to miscommunication or misunderstanding of client's requirements

The correct answer is 'Construct validity threat due to miscommunication or misunderstanding of client's requirements'. This scenario represents a communication gap between the team and the client, leading to unmet expectations. This is a construct validity threat where the design and execution of the software don't align with the needs of the client. On the other hand, 'External validity threat due to tester's personal preferences', 'Internal validity threat due to testing tools used', and 'Information bias as feedback is not accepted' are incorrect. External validity threats are about generalizing the findings beyond the scope of the test, which doesn't apply here. Internal validity threats would suggest measurement errors due to tools or procedures, but here the issue is about misaligned requirements. Information bias does not apply as there is no hint in the question text that feedback is being rejected or ignored.

Correct Answer: Definition of Done

The best measure of the completeness and readiness of a product for release in Agile is the 'Definition of Done'. The 'Definition of Done' provides a checklist that items must meet to be considered done. It ensures that all team members have the same shared understanding of what it means for work to be complete. It could include various parameters like coding completed, testing done, documentation finished etc. The other answers are not the correct measures of a product's readiness. 'Story Points' measure the size of a user story but do not indicate completeness of the product. 'Product Backlog' is a list of features or technical tasks which the team maintains and which, in total, represent the work to be done. But having a backlog does not necessarily mean product is ready. 'Velocity' is a measure of the amount of work a Team can tackle during a single Sprint and is the key metric in Scrum, yet it does not directly determine the completeness or the readiness of the product for release.

Correct Answer: Burn-up Chart

In Agile methodologies, a Burn-up Chart is recognized as a better indicator of team's velocity as it measures the amount of work completed over time. This chart will effectively represent their progress, showing both scope changes and the completed work, providing a better visualization. The others like Histogram, Pie Chart and Scatter Plot may provide some insight, but they typically do not provide an ongoing, long-term view of progress and cannot represent the work completed along with the changes in scope, making them less effective in reflecting the team's velocity.