<PRE><B>Question 1161123</B>
&lt;br&gt;
The answer is NOT C.&lt;br&gt;
The brute force method determines the cheapest route by examining ALL POSSIBLE routes.  ABCDA is not the cheapest route.&lt;br&gt;
In a relatively simple graph like this, the cheapest route will be one that does NOT follow the most expensive edge.&lt;br&gt;
In this graph, edge CD is the most expensive.  Answer choices A, B, and C all use edge CD (or DC), so the answer is D none of the above.&lt;br&gt;
This graph is small enough it is not very difficult to list all possible circuits and find the cost of each.&lt;br&gt;
ABCDA
ABDCA
ACBDA
ACDBA
ADBCA
ADCBA&lt;br&gt;
Note that this list of all 6 circuits is actually 3 different circuits, each listed twice, in opposite orders.&lt;br&gt;
The cheapest route is either of the two that do not use edge CD: ACBDA or ADBCA -- which again are the same circuit in opposite directions.&lt;br&gt;
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