One may conclude that poetic conventions were being challenged by the 1850's from:
(A) sales data of music publishers from 1820 to 1860.
(B) sales data of American publishers from 1820 to 1860.
(C) attending a dedication ceremony of a public monument in the 1850's.
(D) attending symphonic concerts in the 1850's.
(E) an analysis of "Out of the Cradle Endlessly Rocking."
The correct answer for the question that is being presented above is this one: "(C) attending a dedication ceremony of a public monument in the 1850's." One may conclude that poetic conventions were being challenged by the 1850's from: attending a dedication ceremony of a public monument in the 1850's.
