A queue is implemented using a non-circular singly linked list. The queue has a head pointer and a tail pointer, as shown in the figure. Let n denote the number of nodes in the queue. Let enqueue be implemented by inserting a new node at the head, and dequeue beimplemented by deletion of a node from the tail.Which one of the following is the time complexity of the most time-efficient implementation of enqueue and dequeue, respectively, for this data structure?

A queue is implemented using a non-circular singly linked list. The qu

1.	A queue is implemented using a non-circular singly linked list. The queue has a head pointer and a tail pointer, as shown in the figure. Let n denote the number of nodes in the queue. Let enqueue be implemented by inserting a new node at the head, and dequeue beimplemented by deletion of a node from the tail.Which one of the following is the time complexity of the most time-efficient implementation of enqueue and dequeue, respectively, for this data structure?
A.	θ(1), θ(1)
B.	θ(1), θ(n)
C.	θ(n), θ(1)
D.	θ(n), θ(n)
Answer» C. θ(n), θ(1)