“All of the coolant is at a uniform temperature, Tc”, is this

“All of the coolant is at a uniform temperature, Tc”, is this statement correct according to the assumptions for the Unsteady-state energy balance?

A. True

B. False

I got this question in a national level competition.

My question comes from Solving Unsteady topic in division Unsteady – State Material and Energy Balances of Bioprocess Engineering