[Solution from source] Gravity exerts no torque about the sun, so angular momentum is conserved; at perihelion and aphelion the velocity is perpendicular to the radius, so mv₁r₁ = mv₂r₂ and v₁/v₂ = r₂/r₁. The planet moves faster when closer, so the ratio must exceed 1, which rules out r₁/r₂. Answer (3).