The primary source was created after the declaration of war on Serbia by the country of Austria and Hungary.
Option C is the correct answer.
<h3>What is a primary source?</h3>
A primary source is referred to as the source which was created in the ancient era by the historians of that time.
The country of Austria and Hungary declared the warfare on Servia in the year 1477 and ended in the year 1488. After this, primary sources like artifacts, diaries, biographies, manuscripts, etc. were created.
Therefore, the explanation given in Option C would be the correct answer.
Learn more about the primary source in the related link:
brainly.com/question/24172115
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