Which of the following is/are not a super key if {R, S} is the key in a relational schema X with attributes P, Q, R, S, T, U?
1
{S, P, R, T}
2
{P, S, U, R}
3
{P, Q, U, S, T}
4
{P, Q, R, T}
Which of the following is/are not a super key if {R, S} is the key in a relational schema X with attributes P, Q, R, S, T, U?