Answer: B) The Spinal Chord Explanation: A reflex arc is a neural pathway that controls a reflex. In vertebrates, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord. This allows for faster reflex actions to occur by activating spinal motor neurons without the delay of routing signals through the brain.

The Mariana Trench, in the Pacific Ocean, is the deepest location on Earth. According to the Exclusive Economic Zone (EEZ), the United States has jurisdiction over the trench and its resources. Scientists use a variety of technologies to overcome the challenges of deep-sea exploration and explore the Trench.

The term "overdose" in the context of essential elements for plants suggests an excess or imbalance of nutrients, which can have negative effects on plant health. Among the options given:

(A) Nitrogen

Explanation: While all nutrients are essential for plant growth, an overdose or excessive application of nitrogen (option A) can lead to problems such as nutrient imbalance, environmental pollution, and increased susceptibility to certain diseases. Excessive nitrogen can cause rapid vegetative growth, but it may negatively impact other aspects of plant health, such as root development, flowering, and overall resilience.

Balanced nutrient management is crucial for optimal plant growth, and it's important to consider the specific requirements of each plant species and the soil conditions to avoid nutrient imbalances and potential negative effects on plant health.