v, q, and r are positive integers. If v, q, and r are assembled into the six-digit number vqrvqr, which one of the following must be a factor of vqrvqr?	Choose the correct choice from the following choices
A) 23	B) 19	C) 17	D) 7	E) none of the above
One short way -   vqrvqr = 1000vqr + vqr = (1000+1)= 
<gadget id="calculator">(1000+1)</gadget>
<output>1_001</output>
1001vqr   Therefore any factor of 1001 is a factor of vqrvqr   7 is a factor of 1001   So 7
<result>D</result>
v, q, and r are positive integers. If v, q, and r are assembled into the six-digit number vqrvqr, which one of the following must be a factor of vqrvqr?