Which of the following is not an example of homologous organs

Eye of octopus and eye of mammals are functionally similar,  helping in vision but structurally different hence are analogous and are formed as a result of convergent evolution--Different structures evolving for the same function. Vertebrate hearts, Thorns of Bougainvillea and tendrils of cucurbita and leg of cheetah and flipper of whale are examples of homologous organs based on divergent evolution.