57.
Your Answer is
Correct Answer is A
Explanation
That stack becomes heavy. It is a complete sentence, followed by a comma to indicate that it cannot be a sentence, and items B/C/D are excluded. Item A is actually an omitted independent nominative structure: That stack becomes heavy, (with) its weight (being) a satisfying affirmation of my progress. (The part in brackets is a part that can be omitted)
The structure of independent nominative As follows:
(with)+ N + doing/done/to do/ prepositional phrase/adj./N The independent nominative case acts as an adverbial, which can be placed at the beginning and end of a sentence or in a sentence, separated by commas and sentences open.