Found a way to do it.
<div class="row">
<div class="col-xs-8 col-sm-12 col-xs-push-4 col-sm-push-0">
Content B
</div>
<div class="col-sm-6 col-xs-4 col-xs-pull-8 col-sm-pull-0">
Content A
</div>
<div class="col-sm-6 col-xs-8 col-xs-push-4 col-sm-push-0">
Content C
</div>
</div>