A tester on an Agile project typically performs the following tasks12:

Implementing test strategy: A tester helps to define and implement the test strategy for the Agile project, which includes the test approach, test levels, test types, test techniques, test tools, test environment, test data, test metrics, and test documentation.

Measuring and reporting test coverage: A tester measures and reports the test coverage of the product features and quality attributes, such as functionality, usability, performance, security, etc. Test coverage can be expressed in terms of test cases, test scenarios, test sessions, test conditions, test data, code, etc.

Coaching development team in relevant aspects of testing: A tester coaches the development team in relevant aspects of testing, such as test design, test execution, test automation, test-driven development, behavior-driven development, exploratory testing, etc. A tester also helps the development team to improve their testing skills and practices.

The following tasks are not typically performed by a tester on an Agile project:

Documenting business requirements: Business requirements are usually documented by the product owner or the business analyst, not by the tester. The tester may review and provide feedback on the business requirements, but the tester is not responsible for documenting them.

Executing test-driven development tests: Test-driven development tests are usually executed by the developers, not by the tester. The tester may assist the developers in creating and reviewing the test-driven development tests, but the tester is not responsible for executing them.

Therefore, the correct answer is C, as it contains the tasks that are typically performed by a tester on an Agile project. References: ISTQB Foundation Level Agile Tester Extension Syllabus1, pages 14-15, 18-19, 22-23; ISTQB Agile Tester Sample Exam2, question 17.