Concept:
File opening modes define what operations can be performed on a file.
Step 1: Read mode.
Read mode allows only reading from the file. It does not allow editing or writing.
Step 2: Write mode.
Write mode allows writing, but it may overwrite existing content.
Step 3: Append mode.
Append mode allows adding data at the end of the file.
Step 4: Read-write mode.
Read-write mode allows both reading and writing. Therefore, it allows editing of the file.
\[
\therefore \text{Correct Answer is (D)}
\]