How does garbage collection work in programming languages like Java?

In programming languages like Java, garbage collection is a crucial feature that automatically manages memory by reclaiming it from objects that are no longer needed or in use. When an object is created, it consumes memory, but over time, some objects may become unreachable due to changes in the program state, such as when references to them are lost or when the objects go out of scope.

Garbage collection identifies these unneeded objects and reclaims the memory they occupy, thereby preventing memory leaks—situations where memory is allocated but not released, potentially leading to excessive memory use and application slowdowns. This automatic process allows developers to focus on coding without the overhead of manually managing memory, which is not only error-prone but can also lead to issues like fragmented memory.

The other options do not accurately describe how garbage collection functions in Java. For instance, manual memory management is not part of the garbage collection process, nor does garbage collection inherently optimize code execution speed or use fixed-size arrays to prevent memory leaks. Rather, it specifically targets the identification and destruction of objects that are no longer accessible to the program, thus effectively managing resources and enhancing performance over time.