Defending the BJP decision to replace Sadananda Gowda as Chief Minister in Karnataka, the JD-U on Sunday said the leading NDA party had to take the decision to keep its vote base intact and the flock together ahead of the Presidential election.Asserting that caste is a reality in Karnataka,JD-U president Sharad Yadav said in New Delhi,that the BJP has taken the right decision by replacing Sadananda Gowda with Jagadish Shettar as the party has to keep its Lingayat vote base intact.