Salesforce Platform Developer Practice Exam

What is an accurate statement about variable scope?

1. Sub-blocks cannot reuse a parent block's variable name.

2. A variable can be defined at any point in a block.

3. Parallel blocks can use the same variable name.

4. A static variable can restrict the scope to the current block if its value is null.

The correct answer is: Sub-blocks cannot reuse a parent block's variable name.

An accurate statement about variable scope is that a variable can be defined at any point in a block. This means that within a given block of code, you have the flexibility to declare variables wherever it fits the logic, whether at the beginning or deeper within control structures like loops and conditionals. Understanding this aspect of variable scope is crucial because it allows developers to dynamically manage variable visibility and lifespan throughout their code, enhancing code organization and readability. The other options present concepts that, while related to variable scope, do not accurately capture the fundamental definitions of scope in programming. For instance, sub-blocks can indeed reuse a parent block's variable name, which is typically permitted unless the inner block specifically declares its own variable with the same name, which would then shadow the parent's variable. Similarly, parallel blocks can reference the same variable name because they operate in separate scopes, provided those variables do not conflict with each other. Lastly, the concept of a static variable does not inherently restrict its scope to the current block based solely on its null value. The scope of a static variable is defined by its declaration and generally persists across multiple calls, not contingent upon the value it holds.