A small aquatic plant was put in each of the petri dishes X and Y containing different culture solutions. After six weeks, the plant in dish X had the same number of leaves as earlier, and all leaves were small and yellowish. The plant in dish Y had more leaves of normal size and dark green colour. Which of the following set of elements would be missing in the culture of dish X ?

Options

A. Magnesium, Phosphorus, Nitrogen
B. Potassium, Sulphur, Calcium
C. Iron, Manganese, Boron
D. Copper, Zinc, Chlorine

Answer

To solve the question regarding the aquatic plant in dishes X and Y, we need to analyze the conditions of both dishes after six weeks and determine which elements are likely missing in dish X that would lead to the observed symptoms.

### Step-by-Step Solution:

1. **Observation of Dish X**:
- The plant in dish X had the same number of leaves as earlier.
- All leaves were small and yellowish in color.

2. **Observation of Dish Y**:
- The plant in dish Y had more leaves.
- The leaves were of normal size and dark green in color.

3. **Comparison of Growth**:
- The plant in dish X shows stunted growth (same number of leaves, small size) and chlorosis (yellowing of leaves).
- The plant in dish Y shows healthy growth (more leaves, normal size) and vibrant green color.

4. **Identifying Nutrient Deficiencies**:
- The yellowing of leaves (chlorosis) is often associated with deficiencies in essential nutrients.
- Common nutrients that affect leaf color and growth include nitrogen, magnesium, iron, and manganese.

5. **Determining the Missing Elements**:
- Since the plant in dish Y is healthy, we can infer that the nutrients present in its culture solution are necessary for proper growth and pigmentation.
- The yellowish color in dish X suggests a lack of nutrients that promote chlorophyll production and overall plant health.

6. **Conclusion**:
- The most likely missing elements in dish X that would lead to the observed symptoms (small, yellowish leaves) are magnesium, phosphorus, and nitrogen. These elements are crucial for plant growth and the development of green pigmentation.

### Final Answer:
The set of elements missing in the culture of dish X is **Magnesium, Phosphorus, and Nitrogen**.

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