In females, ovaries produce a hormone that helps in the development of breasts at the onset of puberty. Which hormone is secreted by ovaries for the described function?

Options

A. Testosterone
B. Estrogen
C. Thyroxin
D. Insulin

Answer

To answer the question about which hormone is secreted by the ovaries that helps in the development of breasts at the onset of puberty in females, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for a specific hormone produced by the ovaries that is responsible for breast development during puberty in females.

2. **Identify the Hormones**: We need to consider the hormones that are produced by the ovaries. The main hormones produced by the ovaries include:
- Estrogen
- Progesterone

3. **Evaluate the Functions of Each Hormone**:
- **Estrogen**: This hormone is primarily responsible for the development of secondary sexual characteristics in females, including breast development. It plays a crucial role during puberty.
- **Progesterone**: This hormone is involved in regulating the menstrual cycle and preparing the body for potential pregnancy, but it is not directly responsible for breast development at puberty.

4. **Consider Other Hormones Mentioned**: The question also mentions other hormones:
- **Testosterone**: This is primarily a male hormone and is involved in sperm production.
- **Thyroxine**: This hormone regulates metabolism and is not related to breast development.
- **Insulin**: This hormone is involved in glucose metabolism and storage, not breast development.

5. **Conclude the Answer**: Based on the evaluation, the hormone secreted by the ovaries that helps in the development of breasts at the onset of puberty is **Estrogen**.

### Final Answer:
The hormone secreted by the ovaries that helps in the development of breasts at the onset of puberty in females is **Estrogen**.

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