Petiole is the region of attachment of the leaf with the stem.

The correct answer is option 'D', Petiole.

Leaf Anatomy
Leaves are an essential part of a plant's structure and function. They are responsible for photosynthesis, gas exchange, and transpiration. Understanding the anatomy of a leaf helps us understand its various parts and their roles.

Leaf Structure
A leaf consists of three main parts: the leaf base, the petiole, and the lamina.

1. Leaf Base:
- The leaf base is the region of attachment of the leaf with the stem.
- It is usually flattened and expanded.
- The leaf base connects the leaf to the stem and provides support to the leaf.
- It may have small leaf-like structures called stipules.

2. Petiole:
- The petiole is a slender stalk that connects the leaf blade or lamina to the stem.
- It acts as a bridge between the leaf and the stem, allowing the leaf to be positioned for maximum exposure to sunlight.
- The petiole contains vascular tissues, including xylem and phloem, which transport water, nutrients, and sugars between the leaf and the rest of the plant.
- Some leaves may lack a petiole and are directly attached to the stem, known as sessile leaves.

3. Lamina:
- The lamina, also known as the leaf blade, is the flattened, expanded part of the leaf.
- It is usually thin, flat, and green, allowing for maximum surface area for photosynthesis.
- The lamina contains chloroplasts, which are responsible for capturing sunlight and converting it into energy through photosynthesis.
- The lamina may have various shapes, such as oval, lanceolate, or palmate, depending on the species of the plant.

Conclusion:
In conclusion, the region of attachment of the leaf with the stem is called the petiole. The petiole acts as a bridge between the leaf and the stem, providing support and allowing for the transport of water, nutrients, and sugars. The leaf base, on the other hand, is the flattened and expanded region of attachment, while the lamina is the flat, green part of the leaf responsible for photosynthesis.

Petiole