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Consider the relation schemas:

Rank (name, rank) and student (name, country), where name in student table is a foreign key in table Rank.

Which of the following TRC Queries displays all the student names from India along with their respective ranks?

  1. $\{ t \mid \exists q \in Rank ( q [name] = t [name] \wedge  t [rank] = q [rank] ) \wedge \exists p \in student (q [name] = p [name] \wedge q [country] = " India ") \}$
  2. $\{ t \mid \exists p \in Rank ( t [name] = p [name] \wedge t [rank] = p [rank] ) \wedge \exists q \in student (p [name] = q [name] \wedge p [country] = " India ") \}$
  3. $\{ t \mid \exists p \in Rank ( p [name] = t [name] \wedge  p [rank] = q [rank] ) \wedge  \exists q \in student (q [name] = p [name] \wedge q [country] = " India ") \}$
  4.  $\{ t \mid \exists p \in Rank ( t [name] = p [name] \wedge  t [rank] = p [rank] ) \wedge  \exists q \in student (q [name] = p [name] \wedge q [country] = " India ")\}$
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option D will be answer......

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