Erin is the manager of gardening supplies wholesaler SpringTime Inc. The company's vision is to become the leading supplier of gardening materials west of the Mississippi River. In assessing the firm's current state, Erin has determined that the firm could differentiate itself from competitors with an easy-to-use online ordering system and a two-day delivery guarantee. To accomplish this, Erin has determined that SpringTime must spend the next two quarters honing its capabilities for sourcing materials quickly and improving its web development competencies. According to the balanced scorecard approach, what is wrong with Erin's thinking?

a. She has not considered the opportunity costs associated with launching an online ordering system.
b. She has not addressed the question of which core competencies the firm needs.
c. She has failed to account for external factors such as customer perceptions and shareholder perceptions.
d. She has not addressed the question of how SpringTime will create value.