Four sepals arranged in two whorls is characteristic of family.

Options

A. Solanaceae
B. Fabaceae
C. Brassicaceae
D. Liliaceae.

Answer

To determine which family of flowering plants is characterized by having four sepals arranged in two whorls, we can follow these steps:

### Step 1: Understand the Arrangement of Sepals
- The question specifies that there are four sepals arranged in two whorls. This means that the sepals are paired, with two sepals in each whorl.

### Step 2: Identify the Families
- We have four options to consider: Solanaceae, Fabaceae, Brassicaceae, and Lilaceae. We need to analyze each family to see if they fit the description.

### Step 3: Analyze Each Family
1. **Solanaceae (Nightshade Family)**:
- Typically has five sepals and does not fit the description of having four sepals in two whorls.

2. **Fabaceae (Legume Family)**:
- Generally has a variable number of sepals, but it is not specifically known for having four sepals in two whorls.

3. **Brassicaceae (Mustard Family)**:
- This family is known for having four sepals arranged in two whorls (dimerous). This matches the description given in the question.

4. **Lilaceae (Lily Family)**:
- Usually has three sepals or multiples thereof, which does not match the requirement of four sepals in two whorls.

### Step 4: Conclusion
- Based on the analysis, the family characterized by four sepals arranged in two whorls is **Brassicaceae**, also known as the mustard family.

### Final Answer
The correct answer is **Brassicaceae**.

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