What potential issue is highlighted in the $_selectConfig array regarding the 'selected' key?

The potential issue highlighted in the $_selectConfig array regarding the 'selected' key is that it is not properly checking if the key exists before accessing it. This can lead to a PHP notice or warning if the 'selected' key is not set in the array. To solve this issue, you can use the isset() function to check if the 'selected' key exists before accessing it.

$selected = isset($_selectConfig['selected']) ? $_selectConfig['selected'] : '';