The Umbrella Workers Local 18 and Parapluie Co Had Come

The Umbrella Workers Local 18 and Parapluie Co had come to a tentative agreement on major issues and the union members voted in favour of it.But nothing was committed to paper yet.Thinking that there were some important outstanding issues that needed to be resolved,the umbrella workers continued to strike.Parapluie Co accused the union of striking unlawfully,since an agreement was in place.May the union continue to strike?

A) Yes.There has not been a "meeting of the minds," so full consent has not been given to the agreement;therefore,it has not been executed and the union is still entitled to strike.
B) No.Once an agreement has been reached between the parties,they are no longer entitled to strike according to labour legislation in most jurisdictions.
C) Yes.An agreement must be signed in order for it to be executed,therefore the union is still entitled to strike.
D) No.Once the membership has voted in favour of an agreement,the union is bound by the agreement and they are no longer entitled to continue negotiating according to labour legislation in most jurisdictions.
E) No.A collective agreement can be made orally.