Correct Answer: C

Rationale: A) Photosynthesis is the process by which plants, algae, and some bacteria convert light energy into chemical energy to produce glucose from carbon dioxide and water. This process is not related to the breakdown of organic matter by decomposers. B) Bioremediation is the use of living organisms to clean up contaminated environments. While it involves the use of microorganisms to break down pollutants, it is not specifically focused on breaking down organic matter. C) Decomposition is the process by which decomposers such as bacteria, fungi, and other organisms break down organic matter into simpler substances. This process is essential for nutrient recycling in ecosystems. D) Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of nitrite to nitrate by nitrifying bacteria. This process is part of the nitrogen cycle and is not directly related to the breakdown of organic matter.

Correct Answer: C

Rationale: This is an example of a synthesis reaction because simpler substances (water and carbon dioxide) are combined to form a more complex substance (glucose) in the presence of sunlight. Choice A (Decomposition reaction) involves breaking down a compound into simpler substances, which is the opposite of what happens in photosynthesis. Choice B (Combustion reaction) typically involves a substance reacting with oxygen to produce heat and light, not the formation of glucose and oxygen from simpler substances. Choice D (Double displacement reaction) involves an exchange of ions between two compounds, which is not what occurs in photosynthesis.

Correct Answer: D

Rationale: Ionic, covalent, and metallic bonds are all types of chemical bonds that involve the sharing or transfer of electrons between atoms. An ionic bond occurs when one atom donates an electron to another, creating positive and negative ions that attract each other. A covalent bond involves the sharing of electrons between atoms to achieve a stable electron configuration. Metallic bonds are formed between metal atoms where electrons are delocalized and move freely among the metal ions. On the other hand, a gravitational bond is not a type of chemical bond. It refers to the force of attraction between two objects with mass, such as the gravitational force between the Earth and objects on its surface. Therefore, the correct answer is 'Gravitational bond.'

Correct Answer: D

Rationale: The correct answer is 'Fever.' Fever is not a symptom commonly associated with asthma. Asthma symptoms typically include wheezing, difficulty breathing, and chest tightness due to inflammation and narrowing of the airways. Fever is more commonly seen in conditions such as infections or inflammatory diseases rather than asthma. Choices A, B, and C are common symptoms of asthma and are related to the constriction and inflammation of the airways, leading to breathing difficulties and chest discomfort.

Correct Answer: A

Rationale: The correct answer is A: Friction. Friction is the force that opposes the motion of the car on the wet road surface, making it harder for the car to stop. When the car skids, the friction between the tires and the wet road surface is reduced, leading to a loss of traction and making it challenging for the car to come to a halt. Gravitational force (choice B) is the force that pulls objects toward each other due to gravity and does not directly impact the car's ability to stop on a wet road. The normal force from the road (choice C) is the force exerted by the road surface perpendicular to the car's tires and does not play a significant role in stopping the car. Air resistance (choice D) is the force that opposes the motion of an object through the air, but it is not the main force preventing the car from stopping on a wet road.