If an object is thrown straight upward with an initial speed of 8 m/s and takes 3 seconds to strike the ground, from what height was the object thrown?  $\textasciitilde$  $\textasciitilde$  $\textasciitilde$  $\textasciitilde$ 
选项为:A:$$24.2m$$  B:$$21m$$  C:$$23m$$  D:$$2.3m$$  E:$$69m$$  请回答其中一个选项.