Correct Option (c) Air flows from the smaller bubble to the bigger
Explanation:
The excess pressure inside the soap bubble is inversely proportional to radius of soap bubble l.e. , p ∝ 1/r,r being the radius of bubble, It follows that pressure inside a smaller bubble is greater than that inside a bigger bubble.
Thus, if these two bubbles are connected by a tube, air will flow from smaller bubble to bigger bubble and the bigger bubble grows at the expense of the smaller one.