Not a barrier contraceptive:
High-Yield Explanation
Ans. is b, i.e. CentchromanRef: 15th/ed, p222Barrier Methods include:* Condoms (for male use)* Diaphragms (for female use) - Types1. Femshield (female condom)2. Today contraceptive/vaginal sponge3. Vaginal diaphragm/cervical capBesides these spermicidal agents like nonoxynol 9, octoxynol, and menfegol can be added to any of the above barrier contraceptive, to increase its effectiveness.