Answer: A. Ojalá que
Ojalá que mañana tú y yo podamos ir al museo juntos.
Hopefully tomorrow you and I can go to the museum together.
Step-by-step explanation: the subjunctive mode is used in expressions of will, doubt or suggestion. Since the verb in this sentence is in subjunctive mode, "podamos", we have to use an expression of wish. "Ojalá que podamos" that means: Hopefully we can.