12 company problem?

Question

Here is problem statement

http://i218.photobucket.com/albums/cc298/curseofgoldendragon/comp.jpg

please use browsers zoom to see it clearly.

Here is an Analysis for the above problem.
http://s218.photobucket.com/albums/cc298/curseofgoldendragon/?action=view¤t=result.jpg

I could not understand the red marked part of the analysis.
Initially , they used the conditions from the second "Further" block.

and then they used the conditions from the first "Further" block.

I dont understand the red marked part of the analysis....i made a red mark there.

why they are saying ,"...Now from the above result , C must be a construction company,D must be an automobole company ...."

why they used the word "MUST" ???

as we know C,H,I,L are Construction company , so evidently C is a construction company.........i dont understand why they are specifically targetting C and telling its a "must" construction company ? whats the fuss here ?

Answer 1

The misunderstanding is in your statement "as we know C,H,I,L are Construction company".

They are not construction companies but just possible candidates.

C is the only one of them, which is not among candidates for pharma, mobile and auto companies, therefore C MUST be construction company.
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