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.