X connects A and B . X was also the reason why A and B got disconnected .
Solve for A , B and X .

A

B
Quoting Appu ,
“James McNeill Whistler’s (A) lover and model for The White Girl , Joanna Hiffernan (X), also posed for Gustave Courbet (B). Historians speculate that Courbet’s erotic painting of her as L’Origine du monde led to the breakup of the friendship between Whistler and Courbet”
Cracked by Anon , Freestyler , Arun , Appu , Subin , Arcturus and Anil Raghavan .
Joanna Hifferman
Joanna Hifferman
James Whistler – A
Gustave Courbet – B
Joanna Hiffernan – X
James McNeill Whistler’s (A) lover and model for The White Girl, Joanna Hiffernan (X), also posed for Gustave Courbet (B). Historians speculate that Courbet’s erotic painting of her as L’Origine du monde led to the breakup of the friendship between Whistler and Courbet.
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BTW one of the Anons for the Sgt. Pepper’s qn was mine: looks like cookies got cleared from my browser and the name/email fields which are usually auto-filled, were cleared when I submitted the answer.
James Abott McNeil Whistler(A) and Gustave Coubert(B)
X-Joanna Hiffernan
X: L’Origine du monde
A: Whistler
B: Courbet
Joanna Hiffernan supposedly modeled for X and was Whistler’s lover. The explicit nature of painting led to Whistler and Courbet’s separation.
a)james mcneil whistler
b)courbet
x0joanna hiffernan