I can’t walk anymore, I’m . . . . . . . . tired. A. so such B. such C. so D. too

The correct answer is “so”.

The word “so” is used to express a high degree of something. In this case, the speaker is expressing a high degree of tiredness.

The word “such” is used to express a high degree of something, but it is more formal than “so”. It is also used to express a high degree of something that is unusual or surprising. In this case, the speaker is not expressing a high degree of tiredness that is unusual or surprising.

The word “too” is used to express a high degree of something, but it is used to compare two things. In this case, the speaker is not comparing their tiredness to anything else.

The word “such” is not a grammatically correct answer to the question.