Language processors are software programs that translate or convert the source code written in a programming language into machine-readable code that can be executed by the computer. They play a crucial role in the development and execution of programs.

There are three main types of language processors:

1. Assembler:
- An assembler is a language processor that converts assembly language code into machine code.
- Assembly language is a low-level programming language that uses mnemonics to represent machine instructions.
- Assemblers are specific to a particular architecture or family of processors.
- They translate assembly language instructions directly into machine code without any intermediate representation.

2. Compilers:
- Compilers are language processors that translate high-level programming languages into machine code.
- High-level programming languages like C, C++, Java, etc., are easier to understand and write compared to low-level languages like assembly.
- Compilers perform various tasks such as lexical analysis, syntax analysis, semantic analysis, code optimization, and code generation.
- They generate an executable file that can be directly executed by the computer's operating system.

3. Interpreters:
- Interpreters are language processors that directly execute the source code without translating it into machine code.
- They read the source code line by line and interpret each line at runtime.
- Interpreters usually provide a more interactive and dynamic programming environment compared to compilers.
- Examples of interpreted languages include Python, JavaScript, Ruby, etc.
- Interpreted languages are often slower than compiled languages because the source code is not converted into machine code beforehand.

In conclusion, the correct answer is option 'A', assemblers are language processors. However, it is important to note that both compilers and interpreters are also language processors and play vital roles in software development.