Define "load testing".

Load testing is defined as performance testing that simulates multiple users accessing the application. The primary goal of load testing is to determine how well an application can handle concurrent usage under expected conditions. This involves putting a significant load on the system to assess its behavior in terms of response times, throughput, and resource utilization.

The focus is on understanding how the application performs when a large number of users are active, which helps identify potential bottlenecks and ensure the system can maintain performance standards during peak usage. By gathering data during this testing, QA professionals can detect issues related to scalability, stability, and reliability, which are critical for enhancing user experience.

In contrast, the other options do not accurately capture the essence of load testing. Testing for low bandwidth conditions pertains more to network performance testing rather than user load. Similarly, simple database connection checks are not sufficient for evaluating overall application performance. Lastly, ensuring user interface display across various devices relates to usability testing, focusing on design and functionality compatibility rather than application performance under load.