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Here two points to be kept in mind : 

a) If a schedule follows Basic Timestamp  ==> It is conflict serialisable and the equivalent serial schedule is given by the timestamp values of the transactions of the schedule .

b) If a schedule follows Thomas Write ==> It is view serialisable and the  equivalent serial schedule is given by the timestamp values of the transactions of the schedule .

So we first check for conflict serialisability . 

So if we draw the precedence graph of the given schedule we find there is a cycle : T1 -->  T3  --> T1

Hence it is not conflict serialisable and hence not allowed under Basic Timestamp protocol.

For view serialisability the conditions of initial read , updated read and final write should hold . 

    T1                          T2                         T3

  R(X) 

                                R(Y)

                                                             R(Y)

 W(X)                        

                                                             W(X)

                               R(Z)

W(X)

Now here as we can see initial read of X is done by transaction T1 as well as final write is done by T1 . Also r1(X) is at the beginning of transaction so it should be performed before other transaction in serial schedule . But then it will violate final write condition as in this case T1 will come earlier than T3 but it should come after T3 . 

Hence view serial schedule is also not possible and hence not allowed under Thomas Write protocol as well .

Hence C) should be the correct option.

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