GMAT Sentence Correction (SC) | Although formally lasting from June of 1812 until the signing of the T

Hisaarthak299 ,

Look at the modifier "Although formally lasting". As per the rules, it MUST modify the subject of the independent clause.

Now, in option A, we have the subject "the final battle". So, it is trying to convey the meaning that the final battle lasted for so many years but in reality it was the war that lasted while the final battle ended " in the spring of 1815 ".
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