I googled about it and somewhere I read ....
Yes, you can. That is happening in the case of embedded systems
I think NO, it's not possible. Any platform must have an operating system. Or else, your program must itself be an OS. Either soft or hard-wired. Without an operating system your component wouldn't work.
Am I right or can anybody explain me the answer? (I dont have any idea abt embedded systems...)
Of course you can. All a (typical) CPU needs is power and access to a memory, then it will execute its hard-coded boot sequence.
Typically this will involve reading some pre-defined address, interpreting the contents there as instructions, and starting to run them.
These instructions could of course come from a C program, although at this level it's more common to write the very early stages (called bootstrapping) in assembly.
This of course doesn't mean, if I were to read your question title literally, that any C program be run this way. If the program assumes there is an OS, but there isn't, it won't work. This should be pretty obvious.