How to enable "Click-to-play" in Google Chrome Version 43.0.2357.124 (64-bit)?
Google Chrome Version 55.0.2883.95 (64-bit) on macOS Sierra 10.12.2

It looks like the solution for Chrome 43 doesn't work any longer as the Let me choose choose when to run plugin content option is no longer present in the settings. 

At the moment you can:


Open Settings (you can do it by clicking  and then Settings or by clicking ⌘+,).
Click + Show advanced settings.
Enter the Content settings in the Privacy section.
Go to the Flash section and choose Block sites from running Flash.


More information here: https://support.google.com/chrome/answer/142064?hl=en



Google Chrome Version 43.0.2357.124 (64-bit) on OS X Yosemite

Ok, so I've found it. It is not presented as Click to play any longer (it used to be in previous versions of Chrome and is still presented like this in Chromium).

If you want to turn this option on you've got to:


Open Settings (you can do it by clicking ☰ and then Settings or by clicking ⌘+,).
Click Show advanced settings....
Enter the Content settings in the Privacy section.
Enable Let me choose choose when to run plugin content in the Plugins section.




It seems quite obvious now, but I've been trying to find this for a few weeks by now, because it was called Click to play before.