­Five coffee-chicory blends - J, K, L, M, and N - are all priced

 
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The key thing which you have to look for in this question is how Gmat is using Hyphen(-) and Dash(--) to signify something.

Five coffee–chicory blends—J, K, L, M, and N—are all priced differently. 
Between Coffee and Chicory , a Hyphen is provided i.e. it is interlinking the 2 words . So, Increase in coffee means Decrease in Chicory or vice versa. This is what this statement is implying.

After Chicory Blends , a Dash is provided which is sharing with us information wrt to types of Coffee-Chicory blends. 

Statement 1 : Not Sufficient 

Reason : 

In terms of Cost : M>L > (Rest of the three) . We don't know the order of other three. So nothing can be said about the middle term.

Statement 2 : Not Sufficient

Reason : 
 
In terms of Flavour : K & N > J . But we cannot say between K & N which one is first . Also, we have no info wrt to M & L.

Either it can be K>N>J>M>L . So, J is in the middle.

or, it can be M>L>N>K>J . So, N is in the middle .

or, there can be number of ways which you can think of to arrange these types of coffee-chicory blends.

Combining Statement 1 & 2 : Suffcient

Reason : 

M > L in terms of cost.
And the question is informing us Greater the cost, Greater the Coffee proportion.
So, it means Chicory concentration is least in M and second least in L.

K & N > J in terms of Flavour. And the question is informing us Greater the chicory concentration, stronger is the flavour. 
So it means, K & N have more chicory than J and as they have more chicory, it implies there coffee concentration is less. Therefore , there cost will be less than J.

Hence, if you rank them as per cost : M>L>J>(K or N). So, no matter which order you put for K or N,  J will always be in the middle .
Hence, By combining , statement is sufficient.

Therefore , Answer is C.

Hope it helps.