Core idea: Marx used pauperization to denote the worsening economic condition of workers—their real income and living standards decline (absolute or relative impoverishment). Job loss plus price rises directly fit this notion.
Why others are wrong:
(A) {Alienation} = estrangement of workers from product, process, others, and self—primarily a {social/psychic} loss, not specifically income decline.
(B) {Commodity fetishism} = social relations appearing as relations between things—about ideology/appearance, not immediate impoverishment.
(D) {Embourgeoisement} = workers adopting middle-class life-styles—opposite of increasing poverty.
Therefore, \fbox{Pauperization} best captures the situation.