Wastewater is water that has been used and contains various substances, including organic and inorganic compounds. Organic substances in wastewater are those that contain carbon atoms and are derived from living organisms or their byproducts. These substances can have a significant impact on the environment and human health if not properly treated and removed from the wastewater.

There are several organic substances that can be found in wastewater, including:

a) Pesticides: Pesticides are chemical substances used to control or eliminate pests such as insects, weeds, and fungi. They are commonly used in agriculture and can enter wastewater through runoff or improper disposal. Pesticides can be harmful to aquatic life and can persist in the environment for a long time.

b) Herbicides: Herbicides are chemicals used to control or eliminate unwanted plants or weeds. They are also commonly used in agriculture and can enter wastewater through runoff or improper disposal. Herbicides can have negative effects on aquatic plants and animals.

c) Fruit and vegetable waste: Fruit and vegetable waste is a type of organic waste that is generated from the food industry, households, and other sources. It can include peels, seeds, cores, and other parts of fruits and vegetables that are discarded. Fruit and vegetable waste can contain organic compounds such as sugars, starches, and cellulose, which can contribute to the organic load in wastewater.

d) All of the above: The correct answer is option 'D' - all of the above. This means that all the mentioned substances (pesticides, herbicides, and fruit and vegetable waste) are organic substances that can be present in wastewater. These substances can contribute to the organic pollution of water bodies and can have harmful effects on the environment if not properly managed and treated.

In conclusion, organic substances such as pesticides, herbicides, and fruit and vegetable waste can be present in wastewater. It is important to properly manage and treat wastewater to remove these substances and prevent their negative impacts on the environment and human health.