As an experience software testing engineer, quality assurance should be ingrained in your brain and your interviewer is looking to get a sense of your personal feelings towards it in your work with this question. In your answer, be sure to highlight QA's importance in reducing errors, maintaining specifications, testing failure parameters and preventing defects from occurring. In the end, make sure that quality is your mantra in the eyes of your interviewer by giving an example or two of how you put QA in the forefront of your work.
"As a test engineer, I take great pride in my role of ensuring that systems go out to consumers as error free as possible. In my current role, I take the time to learn all of the system specifications that are laid out by our design engineers and customize my testing to follow those specifications."
"In my work throughout my career, quality assurance in my testing was an every minute of every day job on my part. While creating effective testing processes on new software is extremely important in following QA protocols, the recording of defects, issuing of reports and assisting the designers on fixing issues are equally important parts of the process that I'd love to let shine here at MagnaQuest Technologies Pvt.."