Differentiate y = t² (7t² - 8t + 1) with respect to t.
a) (7t - 4) (7t² - 8t + 1)²
b) (7t + 4) (7t² - 8t + 1)²
c) (7t - 4) (7t² - 8t + 1)
d) (7t + 4) (7t² - 8t + 1)