As we know there exists one to one correspondence between :
a) Basic timestamp schedule and conflict serialisable.
b) Thomas Write timestamp schedule and view serialisable
So basically we have to check which one is conflict serialisable..
A) is not conflict serialisable as we have conflict pairs R1(X) - W3(X) and R3(X) - W1(X) .Making the precedence graph cyclic hence and hence not conflict serialisable..
B) is not conflict serialisable as we have conflict pairs R1(X) - W3(X) and W3(X) - W1(X) .Making the precedence graph cyclic hence and hence not conflict serialisable..
D) is not conflict serialisable as we have conflict pairs R1(X) - W3(X) and R3(X) - W1(X) .Making the precedence graph cyclic hence and hence not conflict serialisable..
But C) does not any such conflict pairs which are resulting to cycle in precedence graph..Hence it is conflict serialisable and hence alowed under basic 2PL protocol..
Hence C) option should be correct..