Answer:
The best response to this question: What does this demonstrates, regarding two different types of plants, one with a taproot system and the other with a fibrous root system, who alter their aleady existing root system in order to respond to the changes in their environment, would be: C: structural response to the environment.
Step-by-step explanation:
When talking about plants, and their roots, there are two great categories: the dicot plants, whose root system is known as a taproot, and the monocots, whose root system is fibrous. Each of these systems is separate and particular to each type of plants. They do not combine, and they are unique to each of the categories of plants (dicots, and monocots). However, according to the question, the plants are encountering a climate change, and water has become scarcer. In response to this change, each of the plants, the one with the taproot, and the one with the fibrous root, respond structurally by either enlarging their root further into the soil (taproot), or by sprouting further filaments in the original root system (fibrous root). This, then, shows a structural change and it can happen in plants when environmental changes, not necessarily constant, happen. The plant will only alter its genetic makeup if the changes in environment are continuous and they need deeper changes in the plant, in order to survive.