Object-Oriented Programming

In Java, a public class name must match the filename. If you save a class with a different name than specified, the compiler will fail with a compilation error. The code won't even reach runtime.

A Java class can have only one main method with the signature public static void main(String[] args). This is the entry point that the JVM looks for when executing the class. Overloading main with different parameters is technically possible but only the standard signature serves as the entry point.

Constructor chaining allows calling one constructor from another using the this() keyword in C# or similar syntax in other languages. This avoids code duplication when initializing objects through different constructor overloads.

The Set interface is designed for collections that contain no duplicate elements. Implementations like HashSet enforce uniqueness without imposing any ordering requirement. Lists allow duplicate elements, Maps store key-value pairs, and Vector (a legacy List implementation) also permits duplicates.

In object-oriented programming and Java, a class is not considered a subclass of itself; it is only identical to itself. Inheritance relationships require two distinct classes.

Method overloading requires different parameter lists (different number, types, or order of parameters). Return type alone is insufficient because the compiler wouldn't know which method to call at compile time - the signature must be unique based on parameters, not return type.

Unlike CLDC 1.0, the CLDC 1.1 specification introduced native support for floating-point numbers (float and double data types) and their corresponding operations.

Delegates in .NET are type-safe object references that encapsulate a method. This concept is conceptually identical to function pointers in C or C++.

protected internal combines both access modifiers: accessible within the current assembly (internal) AND to derived classes in other assemblies (protected). private is class-only, protected excludes current assembly, and option D is incorrect.

Serializable is a marker interface - it has NO methods. The JVM checks for this interface at runtime to enable serialization, but there's no requirement to override any methods. The statement claiming it has two methods that must be overridden is false.

The .NET Framework class library is divided into the Base Class Library (BCL), which provides fundamental types, and the Framework Class Library (FCL), which builds on the BCL with domain-specific namespaces. 'Basic Class Library' is not the correct terminology.