Check out example codes for "html drop down list". It will help you in understanding the concepts better.

Code Example 1

<!DOCTYPE html>
<html>
<body>

<h2>The select Element</h2>

<p>The select element defines a drop-down list:</p>

<form action="/action_page.php">
  <label for="cars">Choose a car:</label>
  <select id="cars" name="cars">
    <option value="volvo">Volvo</option>
    <option value="saab">Saab</option>
    <option value="fiat">Fiat</option>
    <option value="audi">Audi</option>
  </select>
  <input type="submit">
</form>

</body>
</html>

Code Example 2

<!-- Answer to: "html drop down list" -->

<label for="items">Choose an item:</label>

<!-- The value for `for=""` and `id=""` has to be same. -->

<select id="items">
  <option value="item-1">Item 1</option>
  <option value="item-2">Item 2</option>
  <option value="item-3">Item 3</option>
  <option value="item-4">Item 4</option>
</select>

Code Example 3

<div class="dropdown">
  <button class="dropbtn">Dropdown</button>
  
<div class="dropdown-content">
    <a href="#">Link 
1</a>
    
<a href="#">Link 2</a>
    <a href="#">Link 3</a>
  </div>
</div>

Code Example 4

<!-- C'est la deuxième valeur -->
<!-- qui sera initialement sélectionnée -->
<select id="monselect">
  <option value="valeur1">Valeur 1</option> 
  <option value="valeur2" selected>Valeur 2</option>
  <option value="valeur3">Valeur 3</option>
</select>

Code Example 5

<!-- O segundo valor estará selecionado inicialmente -->
<select name="select">
  <option value="valor1">Valor 1</option> 
  <option value="valor2" selected>Valor 2</option>
  <option value="valor3">Valor 3</option>
</select>

Code Example 6

<html>
 <head>
   <title>Selection Inputs</title>
 </head>
 <body>
   <form>
     <label for="selector"> <!-- Can add label if want -->
       <p>A "select" element allows users to input from a selection:</p>
       <select id="selector"> <!-- Use "select" to create object -->
         <option>Option 1</option> <!-- Add all applicable options -->
         <option>Option 2</option>
         <option selected>Option 3</option> <!-- add selected to change default from first option -->
         <optgroup label="Group"> <!-- To create nested options for categories use "optgroup" -->
           <option>Option 4</option>
           <option>Option 5</option>
       </select>
     </label>
   </form>
 </body>
</html>

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