Step 1: Clarifying the Query.
The question pertains to the languages or vocabulary associated with "Kokthai krrwikke" within the Sakha context. The provided text indicates that "Kokthai krrwikke" encompasses language categories such as "Ingreji", "Bangla", and "Kubuni" in "Kokborok".
Step 2: Evaluating the Choices.
- (1) Ingreji, Bangla eba Kubuni kokni: Accurate, as the text explicitly names these languages as components of the vocabulary classification for "Kokthai krrwikke".
- (2) Bangla kokni: Inaccurate, as it represents only one of the mentioned languages.
- (3) Ingreji kokni: Inaccurate, as it omits other relevant languages like "Kubuni".
- (4) Bodo kokni: Inaccurate, as "Bodo" is not identified in the text as part of "Kokthai krrwikke".
Step 3: Final Determination.
Consequently, the correct selection is "Ingreji, Bangla eba Kubuni kokni", as these are directly specified as constituent elements of the language stock for "Kokthai krrwikke".