Option 4). is the correct answer.

Marketing plan involves various steps as given below:

1.) Marketing research: In which marketers try to identify the target audience, industrial trend, consumer behavior about a particular product, market potential and competitors.

2.) Brand positioning: In this step, marketers position their brand before target audience and also differentiate their products from the competitors in the market.

3.) Competitive analysis: In this step,marketer analyzes the competitors in the market and develops the product and services that are different from their competitors.

4.) Marketing strategy: After analysis, marketer develops a unique strategy to market and distribute its product using various promotion or distribution channel. In this step, marketing managers develop the channel design to market their product.

5.) Budgeting: In this stage, marketer decides the expenditure of total marking process and also evaluate the expected total return on investment.

6.) Monitoring and evaluation: In this stage, marketer monitors the step by step implementation of the plan and their responses and also evaluate the total outcome of the marketing process.

Therefore, in the steps of marketing, the channel design is related to the marketing process, strategy development and positioning of the brand but not related to pricing strategy.

Hence, option 4). Pricing is the correct answer.