It's unbelievable to see that most people have got the wrong answer.
Most of the people have answered "an"...which is correct. I do not understand what you are trying to say udaraa.
You won't say 'an unit', will you?
I can't believe this either. The correct answer is "a". "a" is always used in front of words that sound like "u". The rule of using "an" before a consonant doesn't apply. Where did you all go to school?
The same way as you wouldn't say "an useful".
Being or seeming to be everywhere at the same time; omnipresent: "plodded through the shadows fruitlessly like an ubiquitous spook" (Joseph Heller).
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