Answer:
Direct benefits
Step-by-step explanation:
The direct benefits model of sexual selection refers to the selection by females based on the personal needs and requirements of the female. These personal requirements often refer to the sexual needs and nuptial gifts like a material that improves the health of the female etc. Here, the provided description refers to the physical aspects of the male and the territory the male possess. Therefore, the personal needs of the female are not considered in the described sexual selection for mating between fiddler crabs hence, direct benefits model is least likely to impact this mating system.