Can you please help me select the correct options and expalin why. Thanks

If | have a discrete random process (Xn)nz0 on two states where for each n, _X,, is independent of Xn3; An4;---Ag when conditioned on _X,,_) and X,,_9, then a. This processis a Markov chain because the future is independent of the past conditioned on the present. b. This process is not a Markov chain but it can be turned into a Markov chain on 4 states. c. This process is a Markov chain because although it does not fit the exact definition, the way it differs is just a technicality. d. This process is not a Markov chain because it does not fit the mathematical definition and this definition is quite strict. @. This process is not a Markov chain but it can be turned into a Markov chain on 3 states