In how many ways can the letters of the word ABACUS be rearranged such that the vowels always appear together?
Choose the correct choice from the following
A) 6! / 2!	B) 3! * 3!	C) 4! / 2!	D) (4! * 3!) / 2!	E) (3! * 3!) / 2!
Explanatory Answer   Step 1: Group the vowels as one unit and rearrange   ABACUS is a 6 letter word with 3 of the letters being vowels.   Because the 3 vowels have to appear together, let us group the AAU as one unit.   There are 3 consonants in addition to one unit of vowels.   These 4 elements can be rearranged in 4! ways.   Step 2: Rearrange the letters within the unit containing the vowels   The 3 vowels can rearrange among themselves in 3!/2! ways as "a" appears twice.   Hence, the total number of rearrangements in which the vowels appear together is 4!∗3!/2!   Choice (4! * 3!) / 2!
<result>D</result>
In how many ways can the letters of the word ABACUS be rearranged such that the vowels always appear together?