（1） ABC is the base word.
（2） If C immediately follows B， then C can be moved to the front of the code
word to generate another word.
From （1）， we cannot determine whether CAB is a code word since （1） gives no
rule for generating another word from the base word. This eliminates A and D
……
Turning to （2）， we still cannot determine whether CAB is a code word since n
ow we have no word to apply this rule to. This eliminates B.
However， if we consider （1） and （2） together， then we can determine whether
CAB is a code word：
From （1）， ABC is a code word.
From （2）， the C in the code word ABC can be moved to the front of the word：
CAB.
Hence， CAB is a code word and the answer is C.
UNWARRANTED ASSUMPTIONS
Be extra careful not to read any moresintosa statement than what is given.
？The main purpose of some difficult problems is to lure yousintosmaking an u
nwarranted assumption.
If you avoid the temptation， these problems can become routine.
Example 6： Did Incumbent I get over 50% of the vote？
（1） Challenger C got 49% of the vote.
（2） Incumbent I got 25，000 of the 100，000 votes cast.
If you did not make any unwarranted assumptions， you probably did not find t
his to be a hard problem. What makes a problem difficult is not necessarily
its underlying complexity； rather a problem is classified as difficult if ma
ny people miss it. A problem may be simple yet contain a psychological trap
that causes people to answer it incorrectly.
The above problem is difficult because many people subconsciously assume tha
t there are only two candidates. They then figure that since the challenger
received 49% of the vote the incumbent received 51% of the vote. This would
be a valid deduction if C were the only challenger （You might ask， “What if
some people voted for none-of-the-above？“ But don't get carried away with fi
nding exceptions. The writers of the GMAT would not set a trap that subtle）。
But we cannot assume that. There may be two or more challengers. Hence， （1）
is insufficient.
