Which sentence uses quotation marks correctly?

a.
before our trip to the vatican museum, we read an article titled "raphael's vision of the human."

b.
when in rome, my uncle and i marveled at michelangelo's statue titled "pietà."

c.
have you seen the play "six characters in search of an author" by luigi pirandello?

d.
one of my favorite movies set in italy is "the bicycle thief."