GMAT Critical Reasoning (CR) | Re: "If true" on questinos

Not sure why this is the correct answer.
D: Carrier pigeons were used in warfare prior to the date of the earliest known record of wartime activity.

IMO, this is not something that can be proved from thearg.
The earliest known records of wartime activities detail the history of the use of carrier pigeons to communicate classified military information.
P may/may not have been used as coi before the mentioned record. In such Qs correct shall be mild. Isn't that D is pretty strong in asserting?

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