The blade is the flattened portion of the leaf. These expanded blades are called lamina which are attached to the plant stem by the petiole. They come in diverse shapes, sizes, and other characteristics. The other choices are just supporting structures of this structure of the plant.
The correct answer is A. Organisms pass on acquired traits to evolve into more advanced life forms. This is because of natural selection and the mantra, "the survival of the fittest".
