Your complex brain thinks and controls your breathing at the same time
Present participle is that verb form which has the suffix -ing. So, the correct answer and the present participle in this sentence is icing.
Frosted would be a past participle.
Were is just past tense of the verb to be.
Resist is an infinitive.
The best answer for this question would have to be D. because in the story the author's desire is to Americanize Chinese cultural traditions. So I would go with D. Hope this helped.