The identity element with respect to the multiplication shown in the diagram below is (begin{array}{cc} otimes & p & p & r & s \ hline p & r & p & r & p
\ q & p & q & r & s\ r & r & r & r & r\ s & q & s & r & qend{array})

A.
p 
B.
q 
C.
r 
D.
s
Correct Answer: Option B
Explanation
The identity element (e) under an operation, say (otimes), is the element such that for any given element under the operation, say a,
(a otimes e = e otimes a = a)
From the table, q is the identity element.
(p otimes q = q otimes p = p)
Same as all through.