Answer:
b.act of disagreement
Step-by-step explanation:
The suffix in "argument" will be "-ment". 'Argue' is a verb and with the addition of the sufix -ment, it becomes a noun. Likewise, to disagree is a verb but with the suffix -ment, it changes into a noun "disagreement". So, "argument" can also be defined as an act of disagreement, representing the literal act of argument.