In this experiment, vaseline/vegetable oil was applied on the upper surface of one leaf (Experimental leaf 1) and on the lower surface of another leaf (Experimental leaf 2). The control leaf did not have any vaseline/vegetable oil applied to it.

When a plant is not watered for several days, it relies on the moisture present in its leaves to survive. The vaseline/vegetable oil creates a barrier on the leaf surface and prevents water loss through transpiration.

Comparing the two experimental leaves, Experimental leaf 2, which had vaseline/vegetable oil applied on its lower surface, will dry up last. This is because the vaseline/vegetable oil on the lower surface will act as a better barrier and reduce the rate of water loss from the leaf.

On the other hand, Experimental leaf 1 only had vaseline/vegetable oil applied on its upper surface. While it will still retain some moisture, it will dry up faster than Experimental leaf 2.

The control leaf, which did not have any vaseline/vegetable oil applied to it, will dry up faster than both experimental leaves.

Therefore, the correct answer is option 2 - Experimental leaf 2 will dry up last