According to Roman Sources, Which May or May Not Be

According to Roman sources, which may or may not be accurate, what were some of the main reasons the Romans assert that they were able to defeat the Etruscans?

A) The Etruscans would not accept the concept of a monarchy.
B) The Etruscans enjoyed life too much to accept the training, fighting, and dying required by sustained warfare.
C) The Etruscans actually admired Roman culture and were ready to become acculturated to it.
D) The Romans had superior weapons and tactics to those of the Etruscans.
E) The Etruscan kingship and leaders of society went into a sharp decline that left the people helpless.