Which practice is prohibited under the Credit Card Act of 2009?

The Credit Card Act of 2009 includes provisions designed to protect consumers from unfair practices related to credit card accounts. One significant aspect of this legislation is the restriction on retroactive interest rate increases. This means that a credit card issuer cannot raise a cardholder's interest rate on existing balances, only for future transactions, unless the cardholder is more than 60 days late on a payment. This protects consumers from being penalized retroactively for past behavior and ensures that they are aware of their interest rates moving forward.

Charging high annual fees for all accounts, offering credit cards with no rewards, and advertising promotional rates that last less than three months, while they may be seen as unfavorable practices, are not outright prohibited under the terms of the Credit Card Act. The legislation specifically targets practices that are deemed harmful or deceptive to consumers, such as the retroactive increase in interest rates, making option B the correct answer.