Explanation:

The correct answer is option 'B' - pane.

Meaning of the Sentence:

The glass broke when it was hit by a stone.

Understanding the Sentence:

In this sentence, the glass is the subject, and the action is the breaking of the glass. The cause of the glass breaking is the stone hitting it.

Meaning of the Word 'Pane':

In the context of this sentence, the word 'pane' refers to a flat piece of glass used in windows or doors.

Explanation:

- When a glass window or door is made, it is divided into smaller sections to form a grid-like pattern. Each individual section is called a 'pane'.
- A pane is a rectangular or square piece of glass that fits into a window or door frame.

Relation to the Sentence:

In the given sentence, the glass is referred to as a 'pane' because it is a part of a larger window or door structure. When the stone hits the glass pane, it breaks.

Alternative Options:

- Option 'A' - 'pain' is incorrect because it does not have any relation to the context of the sentence. 'Pain' refers to physical or emotional discomfort, which is not applicable to the breaking of glass.
- Only option 'B' - 'pane' accurately describes the piece of glass that is broken when hit by the stone.

Conclusion:

Therefore, the correct answer is option 'B' - pane, as it accurately represents the type of glass that broke when hit by the stone.