Q.An online retail company received several customer complaints about unauthorised transactions on their accounts after customers received e-mails, appearing to be from the company, asking them to "verify" their card details by clicking a link. Investigation revealed the e-mails were not genuinely sent by the company.

The correct sequence is Pre-purchase or sale → Purchase or sale → Delivery stage, which follows the natural flow of an online transaction from selecting a product to receiving it.

An online transaction (e-commerce transaction) is completed through three successive stages:

1. Pre-purchase or sale stage — the buyer searches for products, compares options, checks prices and reviews, and decides what to buy. The seller displays products and provides information. This is the first stage.
2. Purchase or sale stage — the buyer places the order, chooses a payment method and makes the payment (net-banking, card, UPI, cash-on-delivery, etc.); the seller confirms the order. This is the middle stage.
3. Delivery stage — the ordered goods or services are packed, dispatched and delivered to the buyer, completing the transaction. This is the last stage. …

The first step in an online transaction is Registration.

An online transaction moves through three broad stages — pre-purchase/registration, placing the order, and payment. The very first step is Registration, in which a prospective buyer creates an account on the website by filling a registration form with details such as name, address, e-mail and password. This account identifies the customer and enables the later steps …

The odd one is Aadhaar card, because it is an identity proof, while the other three are payment/banking cards.

In e-business, online transactions are settled through various electronic payment instruments, especially plastic cards:

• Debit card — lets a customer pay directly from his bank account.
• Credit card — lets a customer pay on borrowed credit from the card-issuing bank, to be repaid later.
• ATM card — used to withdraw cash and carry out banking transactions at an ATM. …

The odd one out is Aadhar card.

In online transactions and banking, various plastic cards are used as payment mechanisms:

• A Debit card allows a customer to pay or withdraw money directly from his own bank account.
• A Credit card allows the holder to make payments on credit up to a sanctioned limit, to be repaid later.
• An ATM card is used to withdraw cash and carry out transactions at automated teller machines. …

The correct answer is registration. To transact online a user must first register on the website by creating an account with a valid ID and password.

An online transaction is a business dealing carried out over the internet, such as buying goods, paying bills or transferring money. Before such a transaction can take place, the user has to complete three broad stages, and the first of these is registration.

• Registration — the buyer fills an online form with personal details (name, address, email, contact number) and creates a login ID and password. This sets up the account needed to place orders and make payments. …