How do pathogens spread diseases?

Pathogens spread diseases primarily through contaminated soil, water, or vectors, which includes insects and other organisms that can carry pathogens from one host to another. This method of transmission is significant because soil and water can easily harbor various microbes, including bacteria, fungi, and viruses, which can then infect plants when they come into contact with these contaminated sources. Vectors, such as aphids or beetles, can facilitate the movement of pathogens across different plants, further contributing to the spread of diseases in crops.

In contrast, while physical damage to crops can indeed make plants susceptible to infections, it is not a method of disease transmission. Competing for resources is a different biological interaction that does not necessarily involve disease spread. The natural growth process of plants does not spread diseases either; instead, it describes how plants grow and develop, which generally does not involve pathogens unless they are present and capable of infection during that growth phase. Thus, the transmission of diseases through contaminated mediums and vectors is the most relevant and accurate choice.