AES uses a $\_\_\_\_\_\_\_\_\_\_\_\_$ bit block size and a key size of $\_\_\_\_\_\_\_\_\_\_$ bits.

a$)128$; $128$ or $256$

b$)64$; $128$ or $192$

c$)256$; $128,192,$ or $256$

d$)128$; $128,192,$ or $256$