OG10-6 it的指代

6. 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

(B)  trying that it metabolize, or render harmless, the . chemical irritant

(C)  attempt to try to metabolize, or render harmless, such a chemical irritant

(D)  attempt to try and metabolize, or render harm­less, the chemical irritating it

(E)  attempt to metabolize, or render harmless, the chemical irritant

dioxin导致了酶的产生，这些酶是生物体的尝试为了新陈代谢（分解），或者使无害，这种化学刺激物。

我的理解是，it是指代production的，也就是说dioxin刺激了production这个过程...不知大家同不同意这个观点...

搜了以前的帖子--大牛如是翻译:

1.the chemical irritant同时是metabolize 与
        render 的受词

2. render O1 OC 2 => render OC2 O1(由轻到重)
    render the chemical irritant harmless => render harmless the chemical irritant

实际上在所有动物的组织中，戴奥辛都能催化酵素，该酵素是具有将化学刺激物促使其新陈代谢、转换成无害。