Final answer:
A feedback loop with both positive and negative signs suggests the potential for both feedback types; however, the nature of the system's response determines its classification. If it amplifies the process, it's positive feedback; if it maintains equilibrium, it's negative feedback. The loop in question helps maintain equilibrium and thus is a negative feedback loop.
Step-by-step explanation:
A feedback loop that contains both a positive sign (+) and a negative sign (−) can be somewhat misleading because these signs may suggest the possibility of both positive and negative feedback mechanisms being present. However, it's important to understand the definitions and outcomes of each type of feedback to determine the correct answer. In a positive feedback loop, the presence of a substance or outcome leads to an increase in its production or occurrence. This can lead to a runaway effect, where the system amplifies itself and diverges further from its baseline state. An example is the rapid growth of bacteria population. In contrast, a negative feedback loop regulates a process by reducing the output or activity when it gets too high and stimulating it when it gets too low, hence maintaining an equilibrium or steady state.
Therefore, we must look at the overall effect of the loop. If the feedback loop leads to increased production and amplification of effects, it is a positive feedback loop. If it serves to regulate and balance the process, bringing it back toward a setpoint or equilibrium, it's a negative feedback loop. The description given suggests that the loop is intended to maintain equilibrium rather than allowing for an exponential runaway, and therefore it would be considered a negative feedback loop.