The correct answer is: D. I shall be obliged by the circumstances to go.
The other options are incorrect because they do not accurately reflect the meaning of the sentence. Option A, “I will oblige the circumstances and go,” suggests that the speaker is choosing to go, while the sentence actually implies that the speaker is being forced to go. Option B, “I shall be obliged to go by the circumstances,” is grammatically incorrect. Option C, “Under the circumstances, I should go,” is a more tentative statement than the sentence, which suggests that the speaker has no choice but to go.
The sentence “Circumstances will oblige me to go” means that the speaker is being forced to go by the circumstances. The speaker does not have a choice in the matter, and they are obliged to go, or forced to go, by the circumstances.