Let A= {1, 2, 3}. The number of relations on A containing (1, 2) and (2, 3) which is reflexive and transitive but not symmetric is :

3

The correct answer is Option (2) → 3

Relations with (1, 2), (2, 3) which is reflexive and transitive only

$R_1=\{(1,1),(2,2),(3,3),(1,2),(2,3),(1,3)\}$

$R_2=\{(1,1),(2,2),(3,3),(1,2),(2,1),(2,3),(1,3)\}$

$R_3=\{(1,1),(2,2),(3,3),(1,2),(2,1),(3,1),(2,3),(1,3)\}$

3 relations