In article model there is a function called getItem($pk) where $pk is article id.
File: components\com_content\models\article.php
Call this function with passing article id. this will return all article related data.
In result you can find links "Link A" or "Link B" in urls variable like below:
$result = $model->getItem($articleId);
$result->urls
contains information related to links "Link A" or "Link B". json_decode this data and use accordingly.