Let's go with this slowly.
"rate of change of P with respect to t" means ΔP/Δt or in differential equation, dP/dt.
"directly proportional to (10 - t)" means that it is equal to a constant multiplied with (10-t).
"inversely proportional to the cube root of P" means that the reciprocal of ∛P is multiplied
Following these deductions, the answer would be E.