Which of the following shows the correct method for calculating the number of atoms per unit cell for the BCC crystal structure? A $1$ whole atom $($in the middle$)+8$ whole corner atoms $=9$ atoms per unit cell

B $1$ whole atom $($in the middle$)+(1/2$ atom within the unit cell$)*(8$ corner atoms$)=5$ atoms per unit cell

C $1$ whole atom $($in the middle$)+(1/4$ atom within the unit cell$)*(8$ corner atoms$)=3$ atoms per unit cell

D $1$ whole atom $($in the middle$)+(1/8$ atom within the unit cell$)*(8$ corner atoms$)=2$ atoms per unit cell