My attempt:
In virtually all types of tissue in every animal species, dioxin induces the production of enzymes that are the organism’s trying to metabolize, or render harmless, the chemical that is irritating it.
(A) trying to metabolize, or render harmless, the chemical that is irritating it the use of trying to is wrong and the use of pronoun it is not claer
(B) trying that it metabolize, or render harmless, the chemical irritant the use of training that is wrong
(C) attempt to try to metabolize, or render harmless, such a chemical irritant the use of attempt to and try to is redundant
(D) attempt to try and metabolize, or render harmless, the chemical irritating it the use of attempt to and try to is redundant and the use of pronoun it is not clear
(E) attempt to metabolize, or render harmless, the chemical irritant this is my answer.