Step 1: Understanding the question context.
This question asks about the languages or word stocks associated with Kokthai krrwikke in the context of Sakha. The passage mentions that Kokthai krrwikke involves language categories like Ingreji, Bangla, and Kubuni in Kokborok.
Step 2: Analyzing the Options.
- (1) Ingreji, Bangla eba Kubuni kokni: Correct, as the passage clearly states these languages are part of the word stock classification for Kokthai krrwikke.
- (2) Bangla kokni: Incorrect, as it only refers to one of the languages involved.
- (3) Ingreji kokni: Incorrect, as it misses other relevant languages like Kubuni.
- (4) Bodo kokni: Incorrect, as Bodo is not mentioned in the passage as part of Kokthai krrwikke.
Step 3: Conclusion.
Thus, the correct answer is Ingreji, Bangla eba Kubuni kokni, as they are directly mentioned as part of the language stock for Kokthai krrwikke.