In basic timestamp ordering, say a transaction T issues write (Q) operation, then which of the below is true?

Question

(TS: time stamp)

If TS (T) < Read-TS (Q), then write is rejected and T is rolled back
If TS (T) < write-TS (Q), then write is rejected and T is rolled back
Both (A) and (B)
None of these

Answer 1

both are true! 
1. a younger transaction has already read the data item, so older transaction is not allowed to update it.
2. a younger transaction has already written the data item, so older transaction is not allowed to write it. 

Basic Timestamp ordering protocol:

Comments

a younger transaction means Read-TS (Q) in option A and Write-TS (Q) in option B ?
so we take it as Write (Q) TS (T) < Read-TS (Q) ?

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Read-TS(Q) = max ( timetimeps of all the transactions which performed a successful read operation on data item Q)

TS < Read-TS(Q) means timestamp of the transaction which is trying to write Q, has lesser timestamp than than the transaction which has performed read  operation successfully.

same in the case of 2nd statement.

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see my updated solution!