Answer: the most affected object by friction is the Y
Step-by-step explanation:
 The fluid friction consists of 2 parts. 
viscous resistance and friction with air. 
assuming that the objects are in contact with the air, the situation is described by the following equation.

with: C= numerical drag coefficient
p= density 
A= Area of the object 
v= velocity 
so assuming the other variables are constants the area of the object is directly proportional to the fluid friction