The logic circuit shown in the diagram directly implements which of the Boolean expressions given below?

$x^{\text{'}}(x+y)$

$x^{\text{'}}((xy{)}^{\text{'}}{x}^{\text{'}}{)}^{\text{'}}$

$x^{\text{'}}+(xy)$

$(x^{\text{'}}y{)}^{\text{'}}(x+y{)}^{\text{'}}$