Answer:
The correct answer is A: Sieve elements and companion cells.
Step-by-step explanation:
In certain types of plants, known as vascular plants, the systems that nutrients follow in order to reach all necessary parts of the plant, and which derive from two different sources: nutrient uptake from the ground through the roots, and nutrient generation through photosynthesis, from the leaves to the rest of the plant, are called the xylem and the phloem. In the case of phloem, this system takes place in the deepest part of the bark of a plant and its purpose it to transport, through a process called translocation, nutrients, particularly sucrose, from the leaves where photosynthesis takes place, to the rest of the plant. As such, the phloem is constituted by cells, particularly conducting cells called sieve elements, parenchyma cells, also known as companion, or albuminous cells, and unspecialized cells.