During development of "Super Mario World", Yoshi's hard saddle was originally which of these?

During the development of Super Mario World, Yoshi's hard saddle was originally a shell. In the game, Yoshi is able to use his saddle to perform a move known as the "shell attack," where he can bounce or stomp on enemies by squishing them between his feet and the hard shell on his back. This mechanic added an extra layer of gameplay strategy, as players could strategically use Yoshi's shell to defeat enemies and traverse the levels. However, in the final version of the game, Yoshi's saddle was changed to its iconic design, which resembles a dinosaur saddle, contributing to Yoshi becoming one of Nintendo's most beloved characters.