∵x−x=0∈I(∴R is reflexive ) Let (x,y)∈R as x−y and y−x∈I(∵R is symmetric) Now x−y∈I and y−z∈I⇒x−z∈I So, R is transative. Hence R is equivalence. Similarly as x=αy for α=1.B is reflexive symmetric and transative. Hence B is equivalence. Both relations are equivalence but not the correct explanation.