Which of the following statement is true ?
A. If A={1,2,3,4,} and R={1,1), (2,2),(2,3), (1,2) } then the relation R on set A is reflexive.
B. Let A ={a,b,c,d) and a relation R on A be defined as follows :
R={a,c), (b,d), (b,c), (c,a), (d,b) }
Then R is a symmetric relation on A.
C. A reflexive relation defined on a non-empty set A is always symmetric.
D. The universal relation defined on a non-empty set A is transitive.
