Pick the odd one out from each series given below and select the correct option.
(i) Scrotum, rete testis, Fallopian tube, vas deferens
(ii) Ovary, uterus, vagina, ejaculatory duct
(iii) Acrosome, Graafian follicle, corpus luteum, cervix
(iv) Prostate, testis, seminal vesicles, Cowper's gland