for option A) R={ } then in this case here relation is symmentric transitive but not reflexive
option B)R={(2,4),(4,6),(2,6)} not any set is possible which is transitive irrefelexive and Antisymmetric
optionC)Intersection part is correct but union can be create pair with violation of antisymmetric
optionD) this is statement is right similarly as option C
correct ANS is A and C