Cabaret. In their introduction, Welch makes reference to Littlefeather's speech, which had just taken place. The transcript of the video is included below:

RW: To all of us, the ladies we have just seen are unforgettable players. To me, they are more than that: they are friends.

GH: At the risk of increasing the suspense for our friends, I'd like to take a moment just to say something. The conventional wisdom is that you're born with talent. Maybe that's so, but talent is unusable and wasted without work, dedication, and a deep feeling for others. The truly talented ladies nominated for best performance by an actress are:

RW: Liza Minnelli in Cabaret. 

GH: Diana Ross in Lady Sings the Blues.

RW: Maggie Smith in Travels With My Aunt.

GH: Cicely Tyson in Sounder.

RW: Liv Ullmann in The Emigrants.

GH: And the winner is.

RW: Hope they haven't got a cause.

GH: Liza Minnelli.

LM: Thank you. Thank you very much. Making the film of "Cabaret" was one of the happiest times of my whole life and I would like to thank everybody connected with it but most especially the artistic staff: Mr. Fosse, and Fred Ebb and John Kander. And thank you for giving me this award. You've made me very happy.]]> https://aaspeechesdb.oscars.org/link/045-3/ ]]>