Question: How can you create a semi-transparent background color?

1. `background-color: hsl(0, 0, 0, 0.5);`
2. `background-color: rgbx(0, 0, 0, 0.5);`
3. `background-color: rgba(0, 0, 0, 0.5);`
4. `background-color: rgba(0, 0, 0, 1);`

Answer: The correct answer of the above question is Option C:`background-color: rgba(0, 0, 0, 0.5);`