Using directives inside or outside namespace in C#: which option is correct?

Hello everyone! I just started learning C# and encountered an unclear situation. In different projects and code examples, I see that using directives are placed differently. Sometimes they are written inside the namespace, and sometimes outside. Here are examples: Option 1 (outside): ```csharp using System; using System.Collections.Generic; namespace MyApp { class Program { static void Main() { } } } ``` Option 2 (inside): ```csharp namespace MyApp { using System; using System.Collections.Generic; class Program { static void Main() { } } } ``` Both options compile and work. But I'm bothered by the question: is there any difference between them? Maybe one option is considered more correct or safer? I've heard that