What must be true for natural selection to happen? a. there cannot be any predators. b. the population must be below carrying capacity. c. all organisms must have the same genotype. d. there must be competition for resources?

The only option given above that is true for natural selection to occur is option d: 'there must be competition for resources'. Natural selection would also occur under predatory pressure. Natural selection occurs through individuals with advantageous characteristics (phenotypes) surviving and passing on their genes (genotypes) to their offspring.