How to Optimize the code with ternary conditional operator ?:

How can I Optimize below code with ternary conditional operator ?:

I am new to Linq Need to know some optimization with operator ?:

Thank you

private string GetFunctionId(FunctionType functionType)
{
string _Id;
int _Count;
if (functionType == FunctionType.abc)
{
_Count = Collection.Where(f => f.Function == functionType).Count();
_Id = String.Format("{0}{1}", "A", Count + 1);
return _Id;
}
else
{
Count = Collection.Where(f => f.Function != TimeProgramFunctionType.FunctionType).Count();
_Id = String.Format("{0}{1}", "B", Count + 1);
return _Id;
}
}

Output should Be

if true A1,A2,A3

else B1,B2,B3