उस शब्द की पहचान कीजिए जिसे 'OBSERVATION' के अक्षरों से बिना किसी पुनरावृत्ति के बनाया जा सकता है।

How many meaningful English words can be formed using the first, fourth, fifth, and eighth letters from the left end of the word 'CONVERSATION', using each letter only once in each word? If no meaningful word can be formed, mark the answer as Y, and if more than three words can be formed, mark the answer as Z. Otherwise, choose the correct answer from the options given below.

If it is possible to make a meaningful 3-letter word with the 3rd, 4th, and 11th letters of the word 'CONTROVERSIAL', what is the middle letter of that word?