Correct Option: B. from a submerged plant Detailed Explanation: Understanding Stomata: Stomata are small openings found on the surface of leaves and stems that allow for gas exchange. They play a crucial role in photosynthesis and respiration by enabling the uptake of carbon dioxide (CO2) and the release of oxygen (O2). Stomata also help in regulating water loss through transpiration. Absence of Stomata: When a leaf lacks stomata, it indicates that the plant has adapted to a specific environment where gas exchange occurs differently. In the case of submerged plants, they are fully underwater, and the need for stomata is significantly reduced or eliminated. Why Option B is Correct: 1. Submerged Plants: Plants that grow entirely underwater, such as certain species of aquatic plants (e.g., Elodea, Vallisneria), do not require stomata because they absorb gases directly from the water through their surfaces. The water contains dissolved oxygen and carbon dioxide, which can diffuse into the plant tissues without the need for stomatal openings. 2. Adaptation to Environment: The absence of stomata in submerged plants is an adaptation to their aquatic environment. Since they are not exposed to air, they do not need to regulate gas exchange in the same way terrestrial plants do. Why the Other Options are Incorrect: Option A: A. from a floating plant - Explanation: Floating plants, such as water lilies or duckweed, typically have stomata on their upper surfaces that are exposed to the air. These stomata allow for gas exchange with the atmosphere. Therefore, a leaf from a floating plant would likely have stomata, making this option incorrect. Option C: C. variegated - Explanation: Variegated plants have leaves with different colors, often due to the presence of chlorophyll in some areas and not in others. The presence or absence of stomata is not directly related to whether a plant is variegated. Variegation does not imply a lack of stomata, so this option is not relevant to the question. Option D: D. from a terrestrial plant - Explanation: Terrestrial plants, which grow on land, typically have stomata to facilitate gas exchange with the atmosphere. They need stomata to take in CO2 for photosynthesis and to release O2. Therefore, a leaf from a terrestrial plant would generally have stomata, making this option incorrect. Summary:

• Stomata are essential for gas exchange in most plants, especially terrestrial ones.
• Submerged plants do not have stomata because they absorb gases directly from water.
• Floating plants and terrestrial plants typically have stomata for gas exchange.
• Variegation does not affect the presence of stomata.

This understanding of stomata and plant adaptations is crucial for recognizing how different environments influence plant structure and function.