Final answer:
In a one-male, one-female primate group, male parental investment would be high. In a multi-male, multi-female group, male parental investment would be medium. In a one-male, multi-female group, male parental investment would be low.
Step-by-step explanation:
In a one-male, one-female primate group, we would expect to see relatively high male parental investment. Since there is only one male, he has the opportunity to devote most of his time and resources to caring for the offspring.
In a multi-male, multi-female primate group, we would expect to see medium male parental investment. With multiple males competing for mates, each male's investment in parental care may be reduced as they focus more on competing for access to females.
In a one-male, multi-female primate group, we would expect to see low male parental investment. Since there are multiple females, the male may mate with multiple females and is not able to provide extensive care for all of the offspring.