Which one can act as semipermeable membrane

Options

A. Phenol layer
B. `Ca_(3)(PO_(4))_(2)`
C. `CU_(2)[Fe(CN)_(6)]`
D. All of these

Explanation

To determine which substance can act as a semipermeable membrane, we need to understand the characteristics of semipermeable membranes and the specific substance mentioned in the question.

### Step-by-Step Solution:

1. **Definition of Semipermeable Membrane**:
A semipermeable membrane is a barrier that allows certain molecules or ions to pass through it while blocking others. This property is crucial in biological and chemical processes, such as osmosis.

2. **Identifying the Substance**:
The transcript mentions "CO2-FECN6" as a substance that can act as a semipermeable membrane. We need to analyze this substance further.

3. **Understanding CO2-FECN6**:
CO2-FECN6 is a compound that is used in a gelatinous state. The gelatinous form allows it to have the necessary properties to function as a semipermeable membrane.

4. **Properties of CO2-FECN6**:
In its gelatinous state, CO2-FECN6 can selectively allow certain ions or molecules to pass through while preventing others, thus fulfilling the criteria of a semipermeable membrane.

5. **Conclusion**:
Based on the information provided, CO2-FECN6 in its gelatinous state can act as a semipermeable membrane.

### Final Answer:
CO2-FECN6 in a gelatinous state can act as a semipermeable membrane.

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