What art piece has moved you most?

When people ask this question the first thing that comes to my mind is Felix Gonzales-Torres' Untitled (Portrait of Ross in LA) created in 1991. Felix Gonzales-Torres was an artist and gay man who lived from 1957-1996. Felix had a long-time partner named Ross who suffered from AIDS and tragically passed away before Felix. In tribute to him Felix created an installation of candy in bright, shiny wrappers roughly the weight of Ross when he first got sick, and museum-goers who viewed the installation were encouraged to take a piece of candy. Over time the pile of candy would dwindle away just like Ross had as he grew more ill. Each day museum staff were to replenish the candy pile back to the instructed weight which in a way allowed Felix to immortalize Ross. I've always thought it was such an impactful installation and it spreads awareness about an important illness as well. That is why it has moved me the most.