Consider a relational database schema with two relations \(R(P, Q)\) and \(S(X, Y)\).
Let \(E = \{\langle u \rangle \mid \exists v\, \exists w\; \langle u, v \rangle \in R \wedge \langle v, w \rangle \in S\}\) be a tuple relational calculus expression.
Which one of the following relational algebraic expressions is equivalent to \(E\)?