Trudy is reading the Irish myth of Aengus Og. In the myth, she read how Aengus fell in love with Caer Ibormeith after dreaming of her. Caer and other girls turned into swans every second Samhain for a year. On what condition did Caer agree to marry Aengus?

A.
if Aengus rescued Caer from the underworld
B.
if Aengus provided Caer with food and shelter
C.
if Aengus picked her in her swan form from among a flock of swans
D.
if Aengus converted her from a sculpture into a real human