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When Munna Bhai joined the university of South Ghatkopar for his M.S., Mr. Irani, his professor, asked him to prove his calibre in a test conducted for the entire class. The class comprised of exactly $10$ students. The test contain exactly $10$ multiple choice type questions. However, Munna as is always the case, managed to get the correct answer-key for all the $10$ questions well before the exam. But in the exam, he wrongly marked exactly one question, on purpose, to avoid raising any suspicion. All the other nine students o the class also formed their respective answer-keys in the following manner. They first obtain the answer-key from one or two of the students, who are called his/her jigris, who already have their answer keys. If a student has two jigris, then he/she first compares the answer from both the jigris. If the key to any question from both the jigris is identical, it is copied, otherwise it is left blank. If a student has only one jigri, then he/she copies the jigri’s keys into his/her copy. However, in the exam, each student intentionally replaced exactly one of the answers, other than a blank, with a wrong answer. It is known that no students replaced the answers to the same question. When Mr. Irani finally assessed all the answer-keys, he formulated the following table, which gives the answer-keys that each of the ten students marked for the $10$ questions- I through X.

Who among the following is not the jigri of any of the ten students?

1. Jassi
2. Praveen
3. Lucky
4. Rahul