My prior post may go too far and create arrays of string variables, so also try the simpler

DIM A$(1), B$(1), C$(1) or even simpler DIM A$, B$, C$

I saw somewhere that Applesoft Basic went to dynamic garbage collection for variable length strings (and if so length was automatic up to some large number of bytes), but have yet to find a reference manual or program example clarifying declaration requirements and rules. In Atari Basic the DIM A$(64) was needed and just created a single string variable holding up to 64 bytes as an example.

Further edited post:

If on your IIc you are using Applesoft BASIC

http://apple2.info/wiki/index.php?title=Applesoft_BASIC#String_expressions_and_Assignments

has some reference info. I get the impression that string variables are dynamically declared and only string arrays need declarations, and that the example by david__schmidt should work without a DIM statement (but what do I know!). Upperlower case may create some issues too.

http://knowledgerush.com/kr/encyclopedia/Applesoft_BASIC_programming_language/

has some historical info on the shift from Integer Basic to Applesoft Basic.