Insert the missing number
10, -20, 40, -80, 160, (....)  Choose the correct choice from the following answers:
A) 320	B) -420	C) 420	D) -320	E) 0
10*-2=-20   -20*-2= 
<gadget id="calculator">-20*-2</gadget>
<output>40</output>
40   40*-2=-80   -80*-2= 
<gadget id="calculator">-80*-2</gadget>
<output>160</output>
160   160*-2=-320   ANSWER:-320
<result>D</result>
Insert the missing number
10, -20, 40, -80, 160, (....)