smashingpumpkins
Teratomas are unusual forms of cancer
because they are composed of tissues such as tooth and bone not normally found in the organ in which the tumor appears.
(A) because they are composed of tissues such as tooth and bone
Eleminated this for the sole reason that tissues at the end felt more appropriate
(B) because they are composed of tissues like tooth and bone that are
like doesn't feel appropriate such as felt much better in the comparison
(C) because they are composed of tissues, like tooth and bone, tissues
These are joining depended clauses with comma which distorts the meaning
(D) in that their composition, tissues such as tooth and bone, is
Similar reasoning as C and 'is' isn't the appropriate word
(E) in that they are composed of tissues such as tooth and bone, tissues
This presents the right meaning and tense
Therefore IMO E