If one company is about to acquire another, which stock should I buy?

Let's say we have two companies and that both their stocks are selling at the same price. Company B has three times the market capitalization of Company A, yet Company A has filed to acquire Company B. uming that all else is equal and that this is all public information, but we guess that Company A will pay a slight premium to buy Company B in order to close, which stock would you invest in before the deal closes?