Your company decides to start the business of selling toys online and shipping globally. A team in-house is in charge of developing an E-Commerce system that supports the new business. As code quality is a priority, the development team is evaluating a solution that can identify or discover defects at the source code level in the fastest way. Which of the following the best strategy?
A. Code review
B. Regression testing
C. Pair programming
D. Unit testing

Kindly be reminded that the suggested answer is for your reference only. It doesn’t matter whether you have the right or wrong answer. What really matters is your reasoning process and justifications.

My suggested answer is C. Pair programming.

Code review can be conducted on a daily, weekly, or monthly basis. It depends on the organization’s needs.

Pair Programming can be viewed as a real-time code review. A peer programmer as the observer can help identify typos, the inconsistent naming convention, logical errors, etc. or suggest more meaningful naming or efficient logics.

Unit testing is written by the developers and conducted with a frequency of minutes.

Regression testing is conducted to prevent a code change from resulting in another software defect. Any code that is related to or depends on the change should be tested repeatedly until no error exists.

Pair programming is an agile software development technique in which two programmers work together at one workstation. One, the driver, writes code while the other, the observer or navigator, reviews each line of code as it is typed in. The two programmers switch roles frequently.

Source: Wikipedia