Final answer:
The term 'Turbidity' is not directly relevant to the Water Framework Directive (WFD) as compared to the other terms, because the WFD is more focused on chemical and ecological status through nutrient management.
Step-by-step explanation:
The Water Framework Directive (WFD) is focused on maintaining high standards of water quality and integrates the management of rivers, lakes, coastal waters, and groundwater. The terms nitrate (A), phosphate (B), ammonia (C), and pH (E) are all highly relevant to the WFD as these factors are indicators of water quality and play a role in processes like eutrophication. However, turbidity (D) is not directly mentioned in the context of the Water Framework Directive's main concerns with chemical status and ecological status of waters, although it can be associated with other directives focusing on particulate matter in water.
Turbidity mainly relates to the clarity of water and the concentration of particulate matter present, which does affect water quality, but not in the same explicit context as nutrient levels, which lead directly to phenomena such as eutrophication and hypoxia. Therefore, in the context of the WFD's primary focus, the answer is D. Turbidity, because it is not as directly associated with the directive's aims of controlling chemical and ecological status through nutrient management.