The correct answer is 4
The reason is that if we are finding the area we need to find the length and width. We can see that they gave us the width which is 4. But the length is separated into two sections of roses and carnations. So we just need to find how long both are. Both combined give us a length of 7 and they "tell us" that the carnations are 3. You can just count and figure out that the roses have a length of 4. You can plug in to make sure it is right. 16 + 12 = 4(4 + 3), 28 = 28