当页面以HTML加载时，如何指定应预先选择一个选项？
使用selected属性指定在HTML中加载页面时应预先选择该选项。您可以尝试运行以下代码以实现所选属性-
示例
<!DOCTYPE html>
<html>
<head>
<title>HTML selected attribute</title>
</head>
<body>
<p>Here's the list of subjects. Select any one:</p>
<form>
<select name = "dropdown">
<option value = "Computer Architecture" selected>Computer Architecture</option>
<option value = "Java">Java</option>
<option value = "Discrete Mathematics">Discrete Mathematics</option>
</select>
</form>
</body>
</html>