Final answer:
The Whataburger Jr. was added to the menu in the 1970s, providing a smaller burger option for customers and reflecting the company's responsiveness to consumer demands.
Step-by-step explanation:
The Whataburger Jr. was added to the Whataburger menu in the option B) 1970s. Whataburger, founded in 1950, has expanded its menu over time to include a variety of burgers and other fast-food options. The introduction of the Whataburger Jr. offered customers a smaller, more manageable burger option, reflecting the company's adaptation to consumer demands for different portion sizes. Since then, Whataburger has continued to remain popular, consistently adding new items to their menu to maintain customer interest and meet evolving taste preferences.