Based on the DES specification, which of the following keys is invalid and will be rejected when used for encryption$/$decryption$?($Select all that apply$)$

Question $8$ Select one or more:

a$.(9696969696969696)16$

b$.(3$B$3$B$3$B$3$B $3$B$3$B$3$B$3$B$)16$

c$.($F$0$F$0$F$0$F$0$ F$0$F$0$F$0$F$0)16$

d$.(0101010101010101)16$

e$.($FEFEFEFE FEFEFEFE$)16$