who tracks the total work remaining to achive sprint goal ? dev team or PO

Perhaps, in a self-organizing team, it could be the first team member who notices that the projection needs updating. Then again, they might decide on some other arrangement. There’s little advantage in constraining a team’s options.

Who is responsible for achieving the Sprint Goal? Is that either the PO, dev team, SM or the entire Scrum Team?

According to the Scrum Guide, "The Development Team tracks this total work remaining at least for every Daily Scrum to project the likelihood of achieving the Sprint Goal".

The sprint goal tracking is by Dev team , while the goal at the product level will be tracked by the PO during sprint review. Chek Scrum guide for the below two topics .

Monitoring Progress Toward Goals

Monitoring Sprint Progress

I agree, with the statement quoted by Vishwanathan,

"The sprint goal tracking is by Development team , while the goal at the product level will be tracked by the PO during sprint review."

Cheers

What if the question was not only about tracking (administration), but also about taking action when the projection indicates the Sprint Goal will not be met? 

What if the Developers do not react in a case the Sprint is most likely to fail? 

It is still the Developers responsibility to manage the work contained in the Sprint Backlog. 

What if the Developers do not react in a case the Sprint is most likely to fail? 

I don't understand what you mean by fail.  My feelings are that the only failure is when you do not learn. So if Developers were not able to reach the Sprint Goal, I would see that as a failure if there was no discussion on why it occurred and nothing learned to prevent from happening in the future.  

I will also add that in my experience, the few times that the Sprint Goal was missed it was still possible to realize a workable increment of value. It might be less value than originally targeted but it was still valuable and delivered progress.