Scientists think that about 65 million years ago, an asteroid struck Mexico and created a huge cloud of dust in the atmosphere. The dust contained iridium, an
element found in asteroids. The dust cloud blocked the sun, killing most of the
plants on Earth. Plant-eating dinosaurs starved. Without herbivores to eat, meat-
eating dinosaurs died, too. Scientists studied rock layers from the time of the
strike to confirm their theory. What evidence would support the theory that an
asteroid impact could have contributed to the extinction of the dinosaurs?

the two answers are a, the population of birds with large beaks will increase on the island, and c, the trait for large beaks will be passed on to future generations through natural selection. the reason for that is because if the birds that have beaks developed for eating small seeds lose all of their food, they will go hungry and eventually starve because they physically cannot eat the large seeds, therefore making the population of large beaked birds higher. also, if the trait of large beaks are dominant on the island over small beaks, then over time the large beaked birds will reproduce more and more, while the smaller beaked birds will reproduce less and less because they can't survive with the food provided. that leads to the trait of small beaks disappearing and the trait of large beaks taking over the island.