The writer Katherine Mansfield produced a body of work
with a number of titles greater than James Joyce but only half the total number of pages, as many of her pieces are short stories while his are dense novels.
A) with a number of titles greater than
James Joyce but only half the total number of pages, as many
This is an incorrect comparison between Katherine Mansfield's body of work and James Joyce (as a human).
B) containing more titles than James Joyce
had, but Katherine Mansfield wrote only half the total number of pages,
and manyThe original sentence intends to use the "many....novels" clause to express the rationale. "Had" also isn't necessary here.
C) containing
a number of titles that
is greater than James Joyce's, but hers had only half the total number of pages, as many
We finally get the possessive right here but...."a number" and "is" is not the right verb agreement!
D) comprising more titles than
the work of James Joyce, but consisting of only half the total number of pages,
and manyIncorrect comparison between "Katherine Mansfield produced X" and "the work of James Joyce"....
E) comprising more titles than
that produced by James Joyce but consisting of only half the total number of pages,
since many"That'' refers to "[body of work] produced by James Joyce" and is properly aligned with "Katherine Mansfield produced a body of work." The "since" adequately portrays the last clause as a cause/rationale.
E remains.