Final answer:
The excerpts relate to the theme of faith and sin. Without faith, the implication is that one remains in a state of sin, as faith is generally seen as a path away from sin and towards redemption. Therefore, the answer is b) Sin.
Step-by-step explanation:
The question "If our faith is in vain then what are we yet in?" can be aligned with the spiritual or religious concept of sin and its implications on the soul or on faith itself. Drawing upon the quotes provided, it seems that there is an underlying theme of despair and the loss of faith, which often is tied into the condition of 'sin'.
The statement "There is no good on earth; and sin is but a name" suggests a recognition of sin's presence everywhere, implicating that without faith, one may find themselves still entangled within sin. Similarly, the concept that without contrition (the feeling of remorse or guilt for wrongdoings) guilt 'would certainly remain unforgiven' implies that in the context of Christian doctrine, one must confront their sins in order to seek forgiveness.