Read the following excerpt carefully before you choose your answer. This excerpt is taken from an eighteenth-century letter from a president to the citizens of the United States of America.

If we remain one people under an efficient government, the period is not far off when we may defy material injury from external annoyance; when we may take such an attitude as will cause the neutrality we may at any time resolve upon to be scrupulously respected; when belligerent nations, under the impossibility of making acquisitions upon us, will not lightly hazard the giving us provocation; when we may choose peace or war, as our interest, guided by justice, shall counsel.

Which stylistic feature contributes to the rhythm of this sentence?

Inversion of normal subject/verb/object order
Periodic sentence structure
Sentence fragments for emphasis
Repetition of sentence structure