The ancient Awabi civilization practiced such ceremonies as dancing around a pile of
burned wood chips,
what they now commonly call Kaheba in northern Asia and other parts of
the continent.
(A) what they now commonly call -
"they" have no antecedent + the whole phrase is awkward(B) a ceremony that they now commonly call -
"they" have no antecedent; the whole underlying part tries to introduce a noun modifying clause that does not agree in number with the preceding plural noun "ceremonies"(C) now commonly called -
correct(D) and is now commonly called -
Civilization practiced ceremonies such as X and is now called Kaheba - the change of the intended meaning of the initial clause. Kaheba is supposed to refer to the dance, not the civilization(E) which it is now commonly called-
usage of which is wrong, "it" has no clear antecedent