......is the hormone responsible for the expression of secondary sex characteristics in human females.

Options

A. Testosterone
B. Estrogen
C. FSH
D. LH

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the hormone responsible for the expression of secondary sex characteristics in human females.

2. **Identifying Secondary Sexual Characteristics**: Secondary sexual characteristics in females include features such as breast development, pubic hair, and changes in voice pitch that occur during puberty.

3. **Hormonal Influence**: These characteristics are influenced by hormones that are released during puberty.

4. **Key Hormones**: In females, the primary hormones involved in the development of secondary sexual characteristics are estrogen and progesterone, both of which are produced by the ovaries.

5. **Identifying the Main Hormone**: Among these hormones, estrogen (specifically estradiol, a form of estrogen) is the primary hormone responsible for the development of secondary sexual characteristics in females.

6. **Conclusion**: Therefore, the correct answer to the question is "estrogen."

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