Bias by source selection implies that an article outlet ignores sources that goes in favour of an opposing form of view.
It is the process of revealing news stories that is in agreement with a particular agenda. It mostly as a result of an article outlet continuously revealing the stories that is in alignment with majorly one political point of view.
Take for instance, an article might contain a story or study produced by a liberal group while choosing to pass on likely stories and studies produced by the conservative sets. Or, a television news outlet might speak on or report an allegation of corruption against a liberal political candidate and choose to wilfully not report a close allegation report against a conservative candidate
