The answer is D. Conclusion
What are the underlined verbs? Learned, Taught, Helped,
With this, you have to put 'Have' in front of the verbs.
We (have) Learned
Teacher (have) taught us There is no reason to go beyond this, B is the irregular one.
the deeper he goes into Hell, the lower levels of it, the sins become worse. Starting from Limbo, where the sinners haven't committed anything that serious, until he gets to the ninth circle where the worst sinners are.
