In the figure above, a circle is inscribed
题型：单项选择题
问题：
In the figure above, a circle is inscribed in a square with side b and a square with side a is inscribed in the circle. What is the area of the square with side b ？（）
(1)a=4
(2)The radius of the circle is 
A．条件(1)充分，但条件(2)不充分．
B．条件(2)充分，但条件(1)不充分．
C．条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分．
D．条件(1)充分，条件(2)也充分．
E．条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．