Which revision best combines these sentences to improve sentence variety and style? (1 point)
A. Made out of oak I built an extra bookcase because I had too many books; now it just needs to be varnished.
B. I built an extra bookcase made out of oak and it just needs to be varnished. I had too many books.
C. I built an extra bookcase made out of oak. It just needs to be varnished as I had too many books.
D. Because I had too many books, I built an extra bookcase made out of oak; now it just needs to be varnished.