Consider the Java segment:

String line1 = new String("c = 1 + 2 + 3") ;
StringTokenizer tok = new StringTokenizer(line1, delimArg);

For the String line1 to have 4 tokens, delimArg should be:
a. String delimArg = "+=";
b. String delimArg = "123"
c. String delimArg = "c+";
d. String delimArg = " ";

a. String delimArg = "+=";