Okay, let's tackle this question. The question is about Saheli or Centchroman. I remember that Saheli is a contraceptive pill. Wait, but what's in it? Let me think. The options are missing, but I need to figure out the correct answer based on my knowledge.

Saheli is a non-steroidal oral contraceptive. I think it's different from the usual estrogen-progestin pills. Oh right, it contains a synthetic steroid called centchroman. Wait, centchroman is the active ingredient. But maybe it's a derivative of something else. Let me recall: centchroman is a derivative of 19-nor-17α-ethynyltestosterone. Or is it a derivative of another compound? Maybe it's a progestin. Wait, centchroman is a progestin, but it's not a steroid. Wait, no, centchroman itself is a synthetic steroid. Wait, no, maybe it's a non-steroidal compound. Wait, I'm getting confused. Let me check my memory.

Centchroman is a non-steroidal estrogen antagonist. Wait, no, that's not right. Wait, centchroman is a synthetic compound used in oral contraception. It's a derivative of 19-nor-17α-ethynyltestosterone. Wait, maybe it's a progestin. Let me recall. The standard combined pills have estrogen and progestin. But Saheli is a progestin-only pill, a mini-pill. Wait, no, Saheli is a non-steroidal pill. Wait, I think I'm mixing up different types. Let me get this straight.

Saheli is a once-a-week contraceptive pill. The active ingredient is centchroman, which is a synthetic compound. It's a derivative of 19-nor-17α-ethynyltestosterone. So the correct answer would be that it contains centchroman, which is a derivative of that compound. Therefore, the correct option would be the one that mentions centchroman as the active ingredient. The other options might include other hormones like estrogen, progestins like norethindrone, or other compounds. The question is testing knowledge of the composition of Saheli, which is a specific type of contraceptive.

**Core Concept**
Saheli (Centchroman) is a non-steroidal, once-a-week oral contraceptive. Its active ingredient, **centchroman**, acts as a **selective estrogen receptor modulator (SERM)** and **progesterone receptor antagonist**, inhibiting ovulation and altering endometrial receptivity.

**Why the Correct Answer is Right**
Centchroman is a **19-nor-17α-ethynyltestosterone derivative**. It binds to estrogen receptors in the hypothalamus and pituitary, suppressing gonadotropin release. Simultaneously, it antagonizes progesterone receptors in the endometrium, preventing implantation. Its non-steroidal structure distinguishes it from traditional estrogen-progestin contraceptives.

**Why Each Wrong Option is Incorrect**
**Option A:** *Estrogen/progestin combinations* (e.g., ethinyl estradiol + levonorgestrel) are used in combined oral contraceptives, not Saheli.

✓ Correct Answer: C. Ormeloxifene