A population with an equal number of young and mature individuals represents:

Population growth is determined by age structure, which includes three categories: (i) Pre-reproductive (young individuals) (ii) Reproductive (mature individuals capable of reproduction) (iii) Post-reproductive (old individuals no longer reproducing) Expanding Population – More young individuals than mature ones, leading to future growth. Declining Population – Fewer young individuals than mature ones, leading to a decrease over time. Stable Population – Equal numbers of young and mature individuals, meaning birth and death rates are balanced, keeping the population size steady. Extinct Population – No individuals left in the population. Since the given scenario describes a balance between young and mature individuals, it indicates a stable population where the size remains constant over time. Hence, the correct answer is (3) Stable population.