The least possible Venn Diagram for the given statements will be as follows,
I. Some Frogs are Dog→ False (As shown in the figure, no frog is a dog so some frogs cannot be dogs) II. All Tigers are Dog → It is not possible (the part of tiger which is frog is not dog). Hence, false.Hence, ‘Neither conclusion (I) nor conclusion (II) follows’ is the correct answer.