According to the Malthusian model:

The Malthusian model, proposed by Thomas Malthus, outlines the relationship between population growth and food supply. According to this model, human populations tend to grow exponentially (or geometrically), meaning that they can double in size in a fixed period, resulting in rapid increases in population numbers under ideal conditions.

Conversely, the model posits that food supply tends to increase linearly (or arithmetically), which means it increases by fixed amounts over time. This disparity between the rapid growth of populations and the slower, more controlled growth of food resources leads to the potential for a population collapse when the food supply cannot sustain the increasing number of individuals.

This explanation aligns with the correct answer, emphasizing the critical concept in Malthusian theory: the inevitable conflict between exponential population growth and linear food supply growth, leading to issues like famine, disease, and mortality when the population surpasses the available food resources.

The other options do not accurately represent the Malthusian model's foundational ideas. For instance, if both population and food supply were to grow geometrically, this would not highlight the pressing concerns that arise from their unequal growth rates that Malthus originally pointed out.