I think it's C. Heavy means the sigh was long, and obviously loud. Wind through a tomb is used as a metaphor that the sigh was lonely. Lonely means nobody is there, and nobody is there to hear wind go though a tomb, and anyone in the tomb can't hear, because, well, they're dead.
I found this page 111 and it talks about how enrique was very nice to other people and how he was allowed in the shop
Answer:
the author uses dialogue to introduce descriptive details to the reader
(i hope u get it right)