The underlined word with the least negative connotation is "displeased" from sentence (a).
Here's the reasoning:
- Displeased implies a mild level of dissatisfaction or annoyance, which generally carries a less intense and negative emotional weight.
- Infuriated (b) conveys extreme anger and strong negative feelings.
- Irritated (c) suggests a moderate level of annoyance, but it is still more negative than "displeased."
- Exasperated (d) indicates a sense of frustration that includes a level of anger but also a feeling of being overwhelmed.
In contrast, "displeased" suggests a simple disappointment without the strong emotional charge present in the other words.