Support One can never tell whether another person is acting from an ulterior motive; therefore, Support it is impossible to tell whether someone's action is moral, and so Conclusion one should evaluate the consequences of an action rather than its morality.
The author concludes that one should evaluate the consequences of an action instead of its morality.
Why?
Because of an intermediate conclusion: it’s impossible to tell whether someone’s action is moral.
That intermediate conclusion is supported by a premise: it’s impossible to tell whether someone is acting from an ulterior motive.
There are gaps to be bridged between the premise and intermediate conclusion, and between the intermediate conclusion and the main conclusion.
Between premise and intermediate conclusion:
If it’s impossible to tell whether someone’s acting from an ulterior motive, then it’s impossible to tell whether that person’s action is moral.
Between the intermediate conclusion and the main conclusion:
If it’s impossible to tell whether someone’s action is moral, then you should evaluate the action based on consequences instead of morality.
Which one of the following ███████████ ██ ██████ ████ █████ ██ ███████ ███ █████████ ██████
The intention of ██ ██████ ██ █████████████ ███ ██ ██████████ ██ ███ █████████
This strengthens the connection between the premise and the intermediate conclusion. “Indispensable” means necessary. So (A) establishes that if we cannot discern someone’s intention behind an action (such as whether they are acting from an ulterior motive), then we cannot evaluate the action’s morality.
The assigning of ██████ ███ █████ ██ ████ ██ ████ █████████ ██ ███ ██████████ ██ ███ █████ ██ █████ ████████
Doesn’t help reach conclusion. We’re trying to establish that one should evaluate consequences instead of morality. (B) would have us focusing on the assigning of praise/blame; determining who’s at fault doesn’t help us argue that we should evaluate consequences rather than morality.
One can sometimes ████ █████ ███ ███████ ███ █ ██████████ ███████
The argument concerns “another person” and their actions. Whether we can know our OWN motives is irrelevant.
There can be ████ ███████ ████ ███ ███ █████████ ██ █ ████ ███████
Whether an action can be “good” doesn’t help us prove that we can’t know an action is moral. It also doesn’t help us prove that we should evaluate the consequences of an action.
One cannot know ███████ ███████ █████ ███████ ██ █ ██████████ █████████ ██████ ███ █████ ████ ████████████ ████ ████████ ███████ ████
Wrong trigger. The bridge we want to build from the premise to the intermediate conclusion should get us from “can’t know someone’s motive” to “can’t tell whether action is moral.” But (E) starts with “can’t know the consequences”; there’s nothing in the argument that establishes we can’t know the consequences (or that we can know the consequences). (E) also doesn’t help us get to the main conclusion, because we’re not trying to prove that in order to know whether an action is moral, we must know the consequences. The main conclusion is about how we should evaluate consequences.