Choose the grammatically correct sentence.

1) If the Centre and States had got down to dealing with the existing regulations on plastic waste management and municipal solid waste, a ban would not even had become necessary. 2) If the Centre and the States had got down to dealing with the existing regulations on plastic waste management and municipal solid waste, a ban would not even have become necessary. 3) If the Centre and the States had got down to dealing with the existing regulations on plastic waste management and municipal solid waste, a ban would not even have become necessary. 4) If the Centre and the States had got down to dealing with the existing regulations on plastic waste management and municipal solid waste, a ban would not even have become necessary.