What is the main purpose of multi-threading in programming?

The main purpose of multi-threading in programming is to provide simultaneous execution of two or more parts of a program. This capability allows applications to perform multiple tasks at the same time, which can lead to improved performance and responsiveness, especially in environments where tasks can be processed in parallel.

For instance, in a user interface application, multi-threading enables the interface to remain responsive while performing background operations, such as loading data or processing inputs. By dividing a program into multiple threads, the program can better utilize the resources of the CPU, which can lead to more efficient execution, particularly in multi-core processor environments where threads can run concurrently on different cores.

The other options do not accurately describe the primary function of multi-threading. While multi-threading may have some effects on memory usage, such as potentially increasing it due to the overhead of managing multiple threads, that is not its primary goal. Simplifying code structure might be a secondary benefit in some cases, but it is not the main purpose of multi-threading. Limiting program execution to one thread is actually contrary to the fundamental concept of multi-threading, which is designed to enable multiple threads rather than restrict them to a single one.