Choose the correct alternative which will improve the part of the sentence given in quotes.
The gas 'is being seeping' out of the rocks.

Correct option is A

The correct substitution of the quoted words is "is seeping".
Explanation: The phrase "is being seeping" incorrectly mixes progressive and passive aspects. The correct form should either be passive "is being seeped" (which isn't commonly used or correct in this context) or active progressive "is seeping". "Is seeping" correctly describes an ongoing action in the active voice.
Grammatical rule used: Progressive aspect is used to indicate ongoing actions in the present.
Example: Water is seeping through the ceiling.