What is the next number in the sequence : 12,15,21,24,30,33,39,51 __?	Pick:
A) 59	B) 53	C) 57	D) 52	E) 51
next no. = previous + (sum of digits)   12 + (1+2)= 
<gadget id="calculator">12 + (1+2)</gadget>
<output>15</output>
15   15 + (1+5)= 
<gadget id="calculator">15 + (1+5)</gadget>
<output>21</output>
21   21 + (2+1)= 
<gadget id="calculator">21 + (2+1)</gadget>
<output>24</output>
24   24 + (2+4)= 
<gadget id="calculator">24 + (2+4)</gadget>
<output>30</output>
30   30 + (3+0)= 
<gadget id="calculator">30 + (3+0)</gadget>
<output>33</output>
33   33 + (3+3)= 
<gadget id="calculator">33 + (3+3)</gadget>
<output>39</output>
39   39 +(3+9)= 
<gadget id="calculator">39 +(3+9)</gadget>
<output>51</output>
51   51 + (5+1)= 
<gadget id="calculator">51 + (5+1)</gadget>
<output>57</output>
57   ANSWER:57
<result>C</result>
What is the next number in the sequence : 12,15,21,24,30,33,39,51 __?