Match the columns:

Column $I$	Column $II$
$(a)$ The outermost whorl of the flower	$(w)$ Corolla
$(b)$ The second accessory whorl of the flower	$(x)$ Calyx
$(c)$ The essential outer whorl of the flower	$(y)$ Pistil (Gynoecium)
$(d)$ The innermost whorl of the flower	$(z)$ Stamen (Androecium)

(A) The floral parts are arranged in four whorls from outermost to innermost:
$1$. Calyx (sepals) - The outermost accessory whorl $(a - x)$.
$2$. Corolla (petals) - The second accessory whorl $(b - w)$.
$3$. Androecium (stamens) - The essential outer whorl $(c - z)$.
$4$. Gynoecium (pistil/carpel) - The innermost whorl $(d - y)$.
Therefore,the correct match is $(a - x), (b - w), (c - z), (d - y)$.