It is known that the Ganga River is much polluted at Kanpur due to leather industries. A team arrived in July to verify but could not find high pollution. Which is the most appropriate answer from the following?

Correct option is C

Introduction
The observation team arrived in July, which corresponds to the monsoon season in North India. During the monsoon, the Ganga River experiences a very high-water discharge (volume of water). The large influx of rainwater and runoff significantly dilutes the industrial effluents and pollutants (like those from leather industries). Therefore, the concentration of pollutants, when measured, appears lower than during the dry season, despite the pollution source still being present.
Information Booster
· Time of Observation: July is the peak of the monsoon season in the region.
· River Condition: The river experiences a massive increase in water volume (high discharge).
· Effect: The vast quantity of water naturally dilutes the concentration of pollutants and effluents (measured as mg/L or ppm).
· Misleading Reading: The lower pollution reading does not mean the source of pollution (the industries) has stopped, but rather that the pollutants have been dispersed and diluted.
· Dry Season Contrast: Pollution levels are typically much higher and more easily detected in the dry summer and winter months when the river's water level is low.
Additional Points
· Due to government initiative, pollution is controlled (a): While government initiatives are ongoing, a complete control leading to a sudden, significant drop in pollution visible only during a high-flow month is less likely than the simple factor of dilution.
· Due to error in observation of the team members (b): The most appropriate answer should be a verifiable natural/seasonal phenomenon, not an assumption of human error.
· Due to control of directly discharging polluted water in the river (d): A reduction in direct discharge would reduce pollution year-round, not just in July; the temporal factor (July) points strongly to dilution.