The following sentence has been split into four segments. Identify the segment that contains a grammatical/spelling error.
He was lying at / his bed when he / saw the snake entering / through the window.

Correct option is B

Option (b) contains an error.
Error: "Lying at" is incorrect. The correct phrase should be "lying on" because the preposition "on" is used for surfaces like a bed.
Grammatical rule used:
· The preposition "on" is used when referring to resting on a surface (e.g., on the bed, on the table).
· The preposition "at" is used for locations or points in space (e.g., at the door, at school).
Example:
❌ Incorrect: He was lying at the bed.
✔ Correct: He was lying on the bed.