The correct answer is option 2: Absorption of water and fixation of Nitrogen. Cycas is a type of plant and its `coralloid root` serves multiple functions. One of its primary roles is absorbing water from the soil. Additionally, the coralloid root of Cycas plays a significant role in fixing nitrogen. Nitrogen fixation is the process by which nitrogen gas in the atmosphere is converted into a usable form for plants. This is an important function as nitrogen is an essential nutrient required for plant growth and development. It is worth noting that the coralloid root of Cycas does not only aid in water absorption but also contributes to the plant`s nitrogen-fixing abilities.