Let’s check B (“Some learned men are very candid”), A (“All candid men are persons who acknowledge merit in a rival”), and F (“Some persons who recognize merit in a rival are learned”):
- From B, some learned men are in the candid group.
- From A, all candid men are also people who acknowledge merit in a rival, so those learned & candid men are also in this “acknowledge merit” group.
- F then states that some people in the “acknowledge merit” group are learned — which follows from combining A and B.
This forms a consistent logical chain, with no contradictions. Other options mix in statements that deny parts of the chain and break consistency.