DCPIP (dichlorophenol indophenol ) is

Options

A. Inhibitor of electron transport
B. Herbicide
C. Inhibitor of photosynthesis
D. Blue-coloured hill oxidant which becomes colourless on being reduced.

Answer

### Step-by-Step Solution:

1. **Understanding DCPIP**: DCPIP stands for dichlorophenol indophenol. It is a chemical compound commonly used in biological studies, particularly in photosynthesis experiments.

2. **Function of DCPIP**: DCPIP acts as an electron acceptor in the photosynthetic electron transport chain. It is used to measure the rate of photosynthesis by observing the reduction of DCPIP.

3. **Analyzing the Options**:
- **Option 1**: Inhibitor of electron transport. This is incorrect because DCPIP itself is not an inhibitor; rather, it is involved in the electron transport process.
- **Option 2**: Herbicides. This is also incorrect as DCPIP is not used to kill unwanted plants or organisms.
- **Option 3**: Inhibitor of photosynthesis. This option is incorrect as well; DCPIP does not inhibit photosynthesis.
- **Option 4**: Blue colored hill oxidant which becomes colorless on being reduced. This is the correct option. DCPIP is indeed blue when oxidized and turns colorless upon reduction.

4. **Conclusion**: Based on the analysis of the options, the correct answer is that DCPIP is a blue colored hill oxidant which becomes colorless on being reduced.

### Final Answer:
DCPIP (dichlorophenol indophenol) is a blue colored hill oxidant which becomes colorless on being reduced.

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