Use the key features of the polynomial f(x) = 6x^4 + 4x^3 - 5x^2 -2x + 1 to describe its end behavior. A. The left side continues up, and the right side continues up. B. The left side continues down, and the right side continues down. C. The left side continues up, and the right side continues down. D. The left side continues down, and the right side continues up.