Final answer:
The caution in the reading advises against omitting challenging goals when planning, emphasizing the need to set achievable, measurable, and motivational objectives with clear action steps.
Step-by-step explanation:
The caution mentioned in the reading about people limiting themselves before they know what they're getting into is B) Omitting challenging goals. This warns against the tendency to leave out difficult objectives in the planning stage. The guidance provided emphasizes the importance of setting achievable and appropriate goals, and to list the necessary steps to meet those goals for clarity and motivation. It's also recommended to create measurable and motivational goals, defining criteria to assess progress. Reflecting on action steps and setting a target date for completion helps in monitoring progress towards reaching career targets. Additionally, being open to adapt goals as one learns more about their field is vital. Jane's case of underestimating tasks reinforces the need for realistic goal-setting that aligns with one's capabilities and time constraints.