I want in near future get CCNA Cisco Certificate, question is asking to peoples who now have CCNA Certificate.
What knowledge source if is the best and is lined to certificate questions?
People usually recommend these books/software/resources:
You can also take a look at the Cisco Learning Network where you'll find forums, study groups, resources etc.
I think this depends on your level of comprehension.
Some of the topics people need explained to them and others are fine being read in a manual. I know I didn't understand sub-netting until a classmate turned around and said "if you don't do this the routers don't know how to route!".
To accurately pass a CCNA there are principles and skills you need to master, not just answers to test questions. Check out Boson's simulator software and then start looking for books on Amazon or training facilities like Global Knowledge.
Cisco publishes Official CCNA study material. I've found it to be a bit classroom oriented, but has all the relevant and necessary knowledge.
If you have an iPhone or iPad, this app might be extremely useful.
https://itunes.apple.com/us/app/ccnax-exam-prep/id791154352?mt=8