The word "pensive" refers to a state of being deeply thoughtful, often in a serious or reflective manner. It signifies a mood where a person is immersed in contemplation or introspection. Among the given options, the only word that accurately captures the pensive meaning is "thoughtful". Therefore, option c is the correct choice.

Analysis of Other Options

• Option a: Tardy
  The word "tardy" means being delayed or late beyond an acceptable timeframe. For instance, "The tardy response from the team delayed the project's completion." This does not align with the pensive meaning, making it an incorrect choice.
• Option b: Confident
  "Confident" describes a feeling of assurance or trust in one’s abilities or outcomes. For example, "She felt confident about her presentation." This meaning differs significantly from the pensive meaning, so this option is also incorrect.
• Option d: Affectionate
  The term "affectionate" reflects a feeling of love or warmth toward someone or something. For example, "The dog was affectionate toward its owner." This word does not align with the reflective or contemplative nature of the pensive meaning, making it an incorrect option as well.

Key Takeaways

It is important to differentiate between the meanings of the given options to avoid confusion. The word "pensive" is best associated with a thoughtful or reflective state, and among the choices, option c: Thoughtful most accurately represents the pensive meaning.