How does a debit card primarily function for the cardholder?

A debit card primarily functions by providing the cardholder with direct access to their bank accounts. When a cardholder uses a debit card for a transaction, the funds are withdrawn directly from their checking or savings account, allowing for real-time access to their account balance. This immediate deduction ensures that the cardholder can only spend what they have available in their accounts, promoting responsible spending.

This function of accessing bank accounts differentiates debit cards from credit cards, which extend credit to the user for future purchases. Additionally, while some debit cards may offer rewards programs, this feature is not inherent to all debit cards and is not the primary function. The option mentioning international transactions suggests exclusivity, which does not accurately represent the versatility of debit cards in terms of functionality. Thus, the correct answer focuses on their main role in providing access to the cardholder's funds.