This is my bet too for under 3.5 goals as this is a safe bet on these two teams that have been playing very badly this tournament.
Chile are defending champions?
They sure do not look like they are 
Chile are defending champions?
They sure do not look like they are Do you know that these tournaments take place every 4 years?, and that 4 years is a lot in soccer? ...
What are the odds for under 3.5 goals?, I think it is not worth the risk, Bolivia is a very weak team, specially out of their land, and I have seen plenty of their matches ending with a lot of goals (not only with them being trashed, but with scores like 4 - 3 or 2 - 4).
https://en.wikipedia.org/wiki/2015_Copa_Am%C3%A9rica
Chile was host country and won it so they are defending champions of the Copa America title
You must be thinking of The World Cup which runs every 4 years. This one runs every few years.