Read the last paragraph of the passage. What did Adams mean when he wrote "Day's Transaction"?

On July 3, 1776, John Adams wrote to his wife, Abigail, that Congress voted for independence on July 2. Congress voted to approve the final version of the Declaration of Independence on July 4, 1776.

. . . The Second Day of July 1776 . . . will be celebrated, by succeeding Generations, as the great anniversary Festival. It ought to be commemorated, as the Day of Deliverance by solemn Acts of Devotion to God Almighty. It ought to be solemnized with Pomp and Parade, with Shews [shows], Games, Sports, Guns, Bells, Bonfires and Illuminations from one End of this Continent to the other from this Time forward forever more. You will think me transported with Enthusiasm but I am not. I am well aware of the Toil and Blood and Treasure, that it will cost Us to maintain this Declaration, and support and defend these States. Yet through all the Gloom I can see the Rays of ravishing Light and Glory. I can see that the End is more than worth all the Means. And that Posterity will triumph in that Day's Transaction, even although We should rue it, which I trust in God We shall not.

A:A. Congress's decision to declare the colonies independent
B:B. Congress's decision to appoint Thomas Jefferson to write the Declaration
C:C. Congress's decision to declare war against Britain
D:D. Congress's decision to celebrate Independence Day as an annual holiday

A:A. Congress's decision to declare the colonies independent