Thinner C's, usually with some tungsten in the windings, will give a more complex tone, and easier articulation even in the higher positions.
Viola Notes on the C String and the G String
<h3> 0 1 2 3 0 1 2 3 </h3><h2><em>
C D E F G A B C</em></h2>
The notes really depend on the type of string you use, I hope this helps.
<em>~</em>Kay
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