Unlike toads, tortoises
a. have amniotic eggs.
b. have lungs.
c. have true bone.
d. have jaws and paired appendages.

The correct answer is (a) have amniotic eggs.

Unlike toads, tortoise have amniotic eggs. Tortoise eggs are surrounded by four fluid filled membranes, chorion, amnion, yolk sac and allantois. Amnion is absent in toad eggs.The amnions acts a cushion for the protection of the developing embryo from the physical damage. These kinds of eggs that contain amnion is called amniotic eggs.

allowed for the prediction of the properties of missing elements.