A baseball would hit the bat harder. This is because the baseball is a lot heavier and more dense than the plastic ball. The keyword that you're looking for is density. The baseball is dense.
B verifying is the answer
A) The lifter's and the barbell's force are equal and opposite in direction
B) The lifter's force is greater than that of the barbell and in the upward direction
C) The barbell's force is greater than that of the lifter and in the downward direction
To solve this problem we will use the concepts related to the uniform circular movement from where we will obtain the speed of the object. From there we will go to the equilibrium equations so that the friction force must be equal to the centripetal force. We will clear the value of the coefficient of friction sought.
The velocity from the uniform circular motion can be described as

Here,
r = Radius
T = Period
Replacing,


From equilibrium to stay in the circle the friction force must be equivalent to the centripetal force, therefore


Here,
Coefficient of friction
N = Normal Force
m = mass
v = Velocity
r = Radius
The value of the Normal force is equal to the Weight, then

Rearranging to find the coefficient of friction

Replacing,


Therefore the minimum coefficient of friction to prevent the cat from sliding off is 0.9399