Correct option is B
(a) Pizza : Bite – A bite is an action, not a standard portion of a pizza.
(b) Ice Cream : Scoop – A scoop is a standard portion of ice cream (just like a slice of bread).
(c) Biscuit : Packet – A biscuit is inside a packet, but the packet is not a part of the biscuit.
(d) Cake : Pastry – A pastry is a different baked item, not a portion of a cake.
So, Ice Cream : Scoop best matches the given relationship.