Which of the following is/are evidence of great transformations of organisms?

a. tiktaalik - a fish that had arm bones similar to all tetrapods (land animals).

b. embryos - where the slits (pharyngeal slits/gill slits) become ear bones in humans, but gills in fish

c. archaeopteryx - a transitional organism that had both bird and dinosaur characteristics

d. completely different genes for every distinct feature between organisms.