The correct option is (B) sphere, cube, plate.
Explanation:
Rate of cooling (dθ / dt) ∝ A
Let area of sphere be AS, plate AP and area of cube AC
∵ same mass and same density hence
AS < AC < Ap
∴ (dθ / dt)sphese < (dθ / dt)cube < (dθ / dt)plate
∴ sphere will cool slowest and plate will fastest