All computers manufactured after 1998 have a minimum processing speed of 400 MHz. My computer has a processing speed of 399 MHz.

Which of the following can definitely NOT be concluded from the above statements?
I) My computer was definitely manufactured after 1998.
II) My computer may have been manufactured in 1998.
III) If it had been manufactured a year later, my computer would have had a faster processing speed.

(A) I only

(B) II only

(C) III only

(D) I and III only

(E) II and III only


Confuse with the NOT, please clarify