Rent Receipts For HRA - Cash Bassi Or Accrual Basis

For claiming HRA, rent paid is to be considered on cash basis..
Rent is invariably paid in the beginning of the month.
For your question option at (1) is the correct one.

Thank you Mr. Nathrao. Taking it on cash basis - Is this based on specific wording in any rule/notification or is there any other justification for this?

What is the difference between cash and accrual system?
Under the accrual basis accounting, revenues and expenses are recognized as follows:
Revenue recognition: Revenue is recognized when both of the following conditions are met:
a. Revenue is earned.
b. Revenue is realized or Realisable.
Under the cash basis accounting, revenues is recognized as below:
Revenue recognition: Revenue is recognized when cash is received.
While filing IT returns,you must follow consistent pattern of income recognition.
Rent is an income which is received in advance and 12 month income can be easily shown in the return.(01 Apr -31 Mar)
Logically cash basis is the correct way to show rent income.