The main sources of water are rain and snow which form a part of the
(Biogeochemical cycle, Ecological cycle, Hydrological cycle, Photosynthetic cycle )

Explanation

To solve the question regarding the main sources of water being rain and snow, we need to identify which cycle they belong to among the given options: Biogeochemical cycle, Ecological cycle, Hydrological cycle, and Photosynthetic cycle.

**Step 1: Analyze the options**
- **Biogeochemical cycle**: This cycle refers to the natural pathways through which essential elements and living matter circulate. It includes cycles like the carbon cycle and nitrogen cycle.
- **Ecological cycle**: This cycle involves the recycling of Earth's limited resources, such as water, carbon, nitrogen, and other elements. It is broader and encompasses various ecological processes.
- **Hydrological cycle**: This cycle specifically deals with the movement of water in various forms (liquid, vapor, solid) through the environment. It includes processes like precipitation (rain and snow), evaporation, and condensation.
- **Photosynthetic cycle**: This cycle is related to the process of photosynthesis, where plants convert carbon dioxide and sunlight into sugars and oxygen. It does not pertain to water sources.

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