If a+b+c=21, what is the total number of non-negative integral solutions?	Choose the correct choice from the following options
A) 223	B) 233	C) 240	D) 243	E) 253
Think of it is a problem of diving 21 items to three people A, B &amp; C which may or may not receive an item.   So simply use Combination here as (n-r+1) C (r-1) i.e.   (21+3-1) C (3-1) =&gt; 23 C 2 == &gt; 253 solutions.   ANSW253R:253
<result>E</result>
If a+b+c=21, what is the total number of non-negative integral solutions?