What distinguishes a global variable from a local variable?

The distinction between global and local variables primarily revolves around their scope and lifetime within a program.

Global variables are defined outside of any function or block and can be accessed and modified from any part of the program, which means they can be edited anywhere. This accessibility allows for greater flexibility in terms of sharing data across different functions. However, it can also lead to issues such as unintentional alterations, making debugging more challenging.

In contrast, local variables are defined within a specific function or block and exist only for the duration of that function or block's execution. Their scope is limited to the function in which they are declared, making them inaccessible from outside of that context. This confinement helps to reduce the risk of unintended side effects on the program and encourages modular design.

The other choices do not accurately capture the nature of these variables. Local variables do not exist for the entire lifespan of the program; they are temporary and have a limited scope. Similarly, global variables are indeed modifiable, contradicting the assertion that they cannot be modified. Lastly, local variables are not visible throughout the program, as they are restricted to the function or block they belong to, emphasizing the importance of scope in programming.

Thus, the defining characteristic of global variables allowing them to