Which one of the following is NOT logically equivalent to ¬∃x(∀y(α)∧∀z(β)) ? Gate 2013

Gate question 2013
Which one of the following is NOT logically equivalent to ¬∃x(∀y(α)∧∀z(β)) ?

∀x(∃z(¬β)→∀y(α))
∀x(∀z(β)→∃y(¬α))
∀x(∀y(α)→∃z(¬β))
∀x(∃y(¬α)→∃z(¬β))
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2013