There is an increase in the water level of all the storage tanks that supply drinking water to a city during the last fortnight, and most of the trains were cancelled last week due to waterlogging on the tracks. What is the correct cause and effect relationship between Statement A and Statement B?

Introduction / Context:
This cause and effect question presents two real world observations involving water. Statement A talks about rising water levels in city water tanks. Statement B talks about cancellation of trains because of waterlogging of railway tracks. The task is to decide whether one of these directly causes the other, whether they are separate causes themselves, or whether both are results of the same underlying factor, for example a period of very heavy rain in the region.

Given Data / Assumptions:

• Statement A: There is an increase in water level in all drinking water tanks in the last fortnight.
• Statement B: Most trains were cancelled last week due to waterlogging on the tracks.
• Water levels in tanks rise when there is heavy rainfall or increased inflow.
• Waterlogging on railway tracks typically occurs after heavy or continuous rain.

Concept / Approach:
The core concept is recognising a common meteorological cause. Heavy rainfall over a period of days will both fill surface reservoirs and storage tanks and also cause flooding around low lying transport infrastructure such as railway lines. We must test whether A directly produces B or vice versa. Increased water in storage tanks does not cause waterlogging on railway tracks. Similarly, waterlogging on tracks does not cause storage tanks to fill. Instead, both are clearly effects of a period of strong rain or similar weather event. So the correct classification is that the two statements are effects of a common cause rather than a cause and effect pair between themselves.

Step-by-Step Solution:
Step 1: Interpret Statement A as an effect of heavy rainfall or increased inflow into tanks during the last fortnight.Step 2: Interpret Statement B as an effect of waterlogging which in turn is caused by heavy rain falling on and around the railway tracks.Step 3: Recognise that the time frames overlap: last fortnight and last week, which are consistent with a single extended rainy spell.Step 4: Consider whether increased tank levels could directly cause train cancellations; there is no clear physical or operational link that would make this true.Step 5: Consider whether cancelled trains could directly cause water in city tanks to rise; this also has no reasonable mechanism.Step 6: Conclude that heavy rainfall is a common external factor that simultaneously leads to higher reservoir levels and waterlogging around tracks.

Verification / Alternative check:
Imagine that there was no rain at all. City planners could still increase tank levels by pumping water from a river, but that would not necessarily cause waterlogging near tracks.Similarly, waterlogging on railway lines could be due to a burst water main, but in that case only some local tanks might be affected, not all of them, which does not match the wording.The most natural shared explanation for both widespread waterlogging and increased tank levels is heavy rainfall across the region.

Why Other Options Are Wrong:
Option A is wrong because rising tank levels do not directly result in trains being cancelled; they are separate symptoms of rain.Option B is wrong because train cancellations cannot cause storage tanks to fill with water.Option C is wrong because it says the two are independent causes, but the pattern clearly suggests a shared environmental factor, making them connected as effects.

Common Pitfalls:
A common mistake is to assume that whenever two statements mention water in different contexts, one must cause the other. However, many real situations share weather as a background cause.Another trap is to overlook the timing clues. The fact that both events occur within roughly the same short period makes a single rainy spell as a common cause much more plausible.

Final Answer:
Both statements describe different consequences of heavy rainfall or a similar weather event, so the correct answer is Both Statement A and Statement B are effects of some common cause.