Whats significant about benjamin franklin's "join or die"?

The difference between the use of Join or Die in 1754 and 1765 is that Franklin had designed it to unite the colonies for 'management of Indian relations' and defense against France, but in 1765 American colonists used it to urge colonial unity against the British.

the use of email to replace slower surface mail.

i believe the answer to your question is b. pay your bills early