Infertility can occur in both the sexes due to deficiency of

Options

A. Oxytocin
B. Prolactin
C. LH
D. FSH

Answer

### Step-by-Step Solution:

1. **Understanding Infertility**: Infertility is the inability to conceive after one year of unprotected intercourse. It can affect both males and females.

2. **Identifying Hormones**: The question lists four hormones: oxytocin, prolactin, LH (luteinizing hormone), and FSH (follicle-stimulating hormone). We need to determine which of these hormones, if deficient, can lead to infertility in both sexes.

3. **Role of Oxytocin**: Oxytocin primarily plays a role in childbirth and lactation in females. It is not directly involved in fertility for both sexes.

4. **Role of Prolactin**: Prolactin is mainly involved in milk production in females. While it can affect fertility, its primary function does not relate to both sexes equally.

5. **Role of LH (Luteinizing Hormone)**: LH is important for ovulation in females and testosterone production in males. However, its deficiency does not directly cause infertility in both sexes.

6. **Role of FSH (Follicle-Stimulating Hormone)**: FSH is crucial for the development of ovarian follicles in females and stimulates spermatogenesis (sperm production) in males. Its deficiency can lead to infertility in both sexes.

7. **Conclusion**: Based on the functions of these hormones, the deficiency of FSH is the primary cause of infertility in both males and females. Therefore, the answer is FSH (Follicle-Stimulating Hormone).

### Final Answer:
Infertility can occur in both sexes due to the deficiency of FSH (Follicle-Stimulating Hormone).

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