The curve is defined by x(t)=t3−3t and y(t)=t2. Which statement correctly characterizes the tangent line to the curve at t=1?
a) The tangent line has slope 2, obtained from dtdy evaluated at t=1.
b) The tangent line is horizontal because dxdy=0 at t=1.
c) The tangent line is vertical because dxdy is undefined (division by zero) at t=1.
d) The tangent line has slope 31, found by computing 3t2+3dy/dt at t=1.