Step 1: Look at the term.
We need the full form of E-Learning.
Step 2: Decode the letter E.
The letter $E$ here stands for Electronic. So E-Learning is short for Electronic Learning.
Step 3: What it involves.
It is learning that uses electronic devices like computers, tablets, smartphones, and internet platforms.
Step 4: How it is used.
It allows online classes, virtual classrooms, digital tests, recorded lectures, and distance education.
Step 5: Reject the wrong options.
Extra learning, rote learning, and European learning do not match the letter $E$ standing for electronic.
Step 6: Final answer.
E-Learning refers to Electronic Learning.
\[ \boxed{\text{Electronic Learning}} \]