Which pair is correct?

Options

A. Progesterone `to` steroid
Estrogen `to` Protein
B. Progesterone + Estrogen `to` Protein
C. Progesterone + Estrogen `to` Steroid
D. Progesterone `to` Protein Estrogen `to` Steroid

Answer

To solve the question "Which pair is correct?", we will analyze each option provided in the context of hormones and their classifications.

### Step-by-Step Solution:

1. **Identify the Hormones and Their Classifications:**
- Progesterone: This hormone is classified as a steroid.
- Estrogen: This hormone is also classified as a steroid.

2. **Evaluate the First Pair:**
- The first pair is "Progesterone, Thymsteroid, and Estrogen."
- The classification provided is "protein."
- This is incorrect because both progesterone and estrogen are steroids, not proteins.

3. **Evaluate the Second Pair:**
- The second pair is "Progesterone and Estrogen."
- The classification provided is "protein."
- This is also incorrect as both hormones are classified as steroids.

4. **Evaluate the Third Pair:**
- The third pair is "Progesterone and Estrogen."
- The classification provided is "steroid."
- This is correct since both hormones are indeed steroids.

5. **Evaluate the Fourth Pair:**
- The fourth pair is "Progesterone and Estrogen."
- The classification provided is "protein."
- This is incorrect as both are steroids.

6. **Conclusion:**
- The only correct pair is the third one, where both progesterone and estrogen are classified as steroids.

### Final Answer:
The correct pair is: **Progesterone and Estrogen (both classified as steroids).**