Final answer:
Sexual selection is stronger in species where male variance in reproductive success is greater. If Species 2 has a stronger correlation between mates and offspring, sexual selection and male competition would be more intense in Species 2.
Step-by-step explanation:
Based on the information provided in the question, sexual selection predicts that certain males will have more reproductive success, often due to being bigger, stronger, or more decorated, subsequently resulting in more matings. These traits are advantageous in both male-male competition (intrasexual selection) and in attracting females (intersexual selection). This sexual selection can lead to sexual dimorphism, where males and females have distinct physical characteristics.
Given that the graph in the question (not actually provided) shows the relationship between the number of mates and the average number of offspring for two different species, we infer that the species where males have a greater variance in reproductive success (more mates correlate to significantly more offspring) would experience stronger sexual selection and competition among males. If Species 2 is assumed to show a stronger relationship (not specified in the question), then sexual selection would be stronger for Species 2, and it is expected that males of Species 2 would compete more strongly over access to females, aligning with option C).