Why does the CIA take out Robert Guzman and Arbenez in 1954?

Answer 1

Its Arbenz.
Primarily because large US corporations, especially United Fruit, felt that Arbenz was a Socialist who was going to be a threat to their future profitability.
This was during the era when the CIA were the muscle for corporate America, and took down people who were "too red."

Wikipedia has a good bio on Arbenz:
http://en.wikipedia.org/wiki/Jacobo_Arbenz_Guzm%C3%A1n

Here is a good leftist history of the coup in Guatemala:
http://www.spartacus.schoolnet.co.uk/JFKarbenz.htm

And another from demopedia:
http://demopedia.democraticunderground.com/index.php?title=Jacobo_Arbenz_Guzm%C3%A1n&printable=yes