Picking random chars from char array?

I'm very new to C++ and have a pretty daunting assignment due this week. I won't get into too much detail about it as I don't want work done for me, but can anyone point me in the right direction as to how I would go about picking random characters from a multi-dimensional string array?

char gameZero[16][6] = { {'A','A','C','I','O','T'}, {'A','H','M','O','R','S'}, {'E','G','K','L','U','Y'}, {'A','B','I','L','T','Y'}, {'A','C','D','E','M','P'}, {'E','G','I','N','T','V'}, {'G','I','L','R','U','W'}, {'E','L','P','S','T','U'}, {'D','E','N','O','S','W'}, {'A','C','E','L','R','S'}, {'A','B','J','M','O','Q'}, {'E','E','F','H','I','Y'}, {'E','H','I','N','P','S'}, {'D','K','N','O','T','U'}, {'A','D','E','N','V','Z'}, {'B','I','F','O','R','X'} };

The goal is to print out a 4x4 board of these characters, picking one random character from each array at the start of every game so not one board is the same.

Any advice/tips on how to do this would be greatly appreciated-- thank you!