“Buy it now” refers to which one of the following options?

Answer: Option C

Definition: "Buy it now" is a marketing strategy that encourages customers to make an immediate purchase.

Personal selling: Involves direct interaction between a salesperson and a potential customer, which is not the case here.
Advertising: Focuses on creating awareness and brand image rather than prompting an instant purchase.
Sales promotion: Includes techniques like discounts, limited-time offers, and urgency-based messages such as "Buy it now" to boost immediate sales.
Publicity: Refers to unpaid promotional activities, such as media coverage, which do not involve direct sales encouragement.

The phrase "Buy it now" creates urgency and encourages instant action, which is a key characteristic of sales promotion.

Thus, the correct answer is: Sales promotion (Option C).