Which of the following statements is true of the asthenosphere?
◦ The asthenosphere is composed of continental and oceanic plates.
◦ The asthenosphere is composed only of crust.
◦ The asthenosphere is composed of the crust and a portion of the outer mantle.
◦ The asthenosphere is composed of the inner portion of the mantle and the outer core.
◦ The asthenosphere is composed of outer mantle material.