Answer: Option A. 
Explanation:
The function for the volume of a sphere is given by V(r) = (4/3)πr^3. 
The radius of the sphere is increasing at a rate of 2 mm per second, which means that the radius at time t seconds is given by r(t) = 2t mm.
To find the volume of the sphere at time t, we can substitute the expression for r(t) into the formula for the volume of the sphere:
V(t) = (4/3)πr(t)^3
 = (4/3)π(2t)^3
 = (4/3)π(8t^3)
 = (32/3)πt^3
V(t)= (32/3)πt^3
 (V ∘ r)(t) = V(r(t)) 
 = V(2t) 
 = (32/3)πt^3
Therefore, the function that gives the volume of the sphere at time t is option A.