src/Helpers/Html.php
public static function activeRadio($model, $attribute, $options = [], $encoding = null)
    {
        return static::activeBooleanInput('radio', $model, $attribute, $options, $encoding);
    }
public static function activeRadio($model, $attribute, $options = [], $encoding = null)
    {
        return static::activeBooleanInput('radio', $model, $attribute, $options, $encoding);
    }
Generates a radio button tag together with a label for the given model attribute.
This method will generate the "checked" tag attribute according to the model attribute value.
@param Model $model the model object
@param string $attribute the attribute name or expression. See [[getAttributeName()]] for the format
about attribute expression.
@param array $options the tag options in terms of name-value pairs.
See [[booleanInput()]] for details about accepted attributes.
@param string $encoding

@return string the generated radio button tag