Which of the versions of Counter Strike: Condition Zero is the latest?

Game 2 is standard Counter Strike (latest version 1.6).

Game 1 and 3 are the same, which is Counter Strike :Condition Zero.

You can tell the difference by a couple of things.

First, on game 3, the name is clearly indicated on the score screenshot. Game 3 and 1 shares the same updated player models for the red bandana terrorist.

You can differentiate 1.6 from CZ by the little location written under the minimap.

And to answer your question, Condition Zero is the most recent of the two. CS is 2000 while CZ is 2004.