most likely
iPhone 6 - aluminum chassis $199 for 16 gb.
iPhone 6C - plastic. $99 for 16 gb with 2 yr contract.
iPhone 5C - free on contract
But...what is the 6C? the current iPhone 5C is just the iPhone 5 in a new casing. If they put the 5S internals into the 6C what happens if they release a 6S? 6S and 7C?