(∀X)[Px ⊃ (∃Y)Qxy] ⊃ [(∃X)Px ⊃ (∃X)(∃y)Qxy]

Multiple Choice

(∀x) [Px ⊃ (∃y) Qxy] ⊃ [(∃x) Px ⊃ (∃x) (∃y) Qxy]
-Consider assuming '(∀x) [Px ⊃ (∃y) Qxy]' for a conditional proof of the above logical truth. Which of the
Following propositions is a legitimate second step in that proof?

A) Assume '(∃x) Px' for a nested indirect proof.
B) Assume '(∃x) (∃y) Qxy' for a nested indirect proof.
C) Assume '(∃x) Px' for a nested conditional proof.
D) Assume '(∃x) (∃y) Qxy' for a nested conditional proof.
E) Px ⊃ (∃y) Qyy