Answer: C). The mud particles will increase the turbidity of the water, making it more difficult for plants to photosynthesize.
Step-by-step explanation:
The run off of the red soil and the construction material in the form of mud particles will contaminate the river water. This will increase the turbidity of the water of the river. The turbidity will not allow the penetration of sunlight into the river water as a result the plants will not get sunlight which is necessary for the process of photosynthesis. In the presence of sunlight the green plants prepare their own food by using carbon dioxide and water so as to produce the carbohydrates in the form of food.