What's the difference among these three syntax for option?

Question

As far as I see all of the option tags below do the same thing. I wonder what are their differences and usage.

<datalist id="list">
<option value="1">
<option value="2"><\option>
<option value="3">A text<\option>
<\datalist>

Answer 1

1st option = showing nothing outside of the tag

2nd option = The tag option is ended

3rd option = is showing between of tags "A text"