That would be the answer C and of not it would be D
The values that were typical of Robert Louis Stevenson's age were the honor and morality of one's self and one's family. An individual must never do anything that would diminish reputation but strive to maintain it or better it. Individuals were to be characters of good moral standing. There was a firm belief in the upkeep of outward appearances of dignity and restrain. Individuals were also supposed to uphold the law above all else, except God. In the middle classes, the idea of self-made men and entrepreneurship was born and this fostered the "American Dream".
This sounds like a multiple choice, but if it isn't I'll just say what I think.
"It gives me pleasure" indicates that he is delighted to announce the news to Congress of the removal of the Native Americans. If we were to take away that section from the passage, it would read something like this:
"The benevolent policy of the Government, steadily pursued for nearly thirty years, in relation to the removal of the Indians beyond the white settlements is approaching to a happy consummation."
Now this sounds cheerful enough, because of the words benevolent (charitable) and happy, but the use of the phrase "gives me pleasure" really sets the tone for the paragraph, and let's you know right away how Jackson is feeling about his announcement.
The verb "will attend" is in future tense