Take the task of seating the 8 letters and break it into stages.

We’ll begin with the most restrictive stages.

Stage 1: Choose a consonant for the 1st letter
There are 3 consonants to choose from (Q, T and N)
So, we can complete stage 1 in 3 ways

Stage 2: Choose a consonant for the 8th letter
There are 2 consonants remaining to choose from (since we already used a consonant in stage 1)
So we can complete stage 2 in 2 ways

We now have 6 spaces and 6 letters remaining.

Stage 3: Choose a letter for the 2nd position
We can do this in 6 ways

Stage 4: Choose a letter for the 3rd position
We can do this in 5 ways

Stage 5: We can choose a letter for the 4th position in 4 ways

Stage 6: We can choose a letter for the 5th position in 3 ways

Stage 7: We can choose a letter for the 6th position in 2 ways

Stage 8: We can choose a letter for the 7th position in 1 way

By the Fundamental Counting Principle (FCP), we can complete all 8 stages (and thus arrange all 8 letters) in (3)(2)(6)(5)(4)(3)(2)(1) ways (= 4320 ways)

Answer: B

Note: the FCP can be used to solve the MAJORITY of counting questions on the GRE. So, be sure to learn it.

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