It was difficult to remove my feet as it had got stuck …… in the mud. A. fairly B. greatly C. widely D. firmly

The correct answer is D. firmly.

The other options are not as accurate because they do not convey the idea of being stuck very tightly.

• Fairly means to a moderate extent.
• Greatly means to a very large extent.
• Widely means over a large area.

In this case, the speaker is trying to convey the idea that it was very difficult to remove their feet from the mud. The only option that accurately conveys this idea is firmly.