OE

Floodwaters had already entered the library, but the “hopeful” volunteers are working anyway—they hope to limit the damage. “Ameliorate” and “mitigate” both have the sense of making something better without completely solving it. Note that “exacerbate” means the opposite (to make worse), and “recant” and “forfeit” are negative words that don’t fit the sentence (you could “recant” your former statements and “forfeit” an athletic competition, for instance). Finally, “recount” means to narrate and nothing in the sentence suggests that the volunteers were discussing the damage to the library