Explanation

The passage conveys the sense that artists are like everyone else in that they have “routines that govern their work.” This view is contrasted with a myth that artists are “somehow different.” In the first blank, only “habit” is something whose rejection presents a contrast with being governed by work routines. Rejecting “latitude” might well match being governed by work routines, and though “materialism” is sometimes rejected by artists, it is not relevant to having work routines. The second blank describes how artists “work as the rest of us do”; only “ploddingly” is consistent with the emphasis on routines and “day by day” work.

Thus, the correct answer is habit (Choice B) and ploddingly (Choice E).
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Why not impetuously. I think it is also consistent with the sentence, no?

No sorry.

The option you cited is completely out of scope.

The artist after all works as everybody does: sporadically, on a daily basis and so forth. Option D is wrong

I also think its sporadically since the word 'ploddingly' and 'day by day' kind of contrasting in this context.

Regards,
Scrat

I THINK B & F is correct answer because at the last it says on their own customs.

Everyone has routines that govern their work. The myth is that artists are somehow different, that they reject (i)________, but of course that’s not true: most artists work as the rest of us do, (ii) ________, day by day, according to their own customs.


Ploddingly = to work with constant and monotonous perseverance;

The key is to understand, actually, the phrase says this: all we do have routines and we believe that artists do not. That is not true. Also they have like all of us.

Sporadically is out of scope.

Regards

The tricky moment here is that the word plodding is an adjective frequently used in different connotation: to walk heavily, (trudge), but here, is someone even does not know the second meaning of the word, plodding, should eliminate the two answer choices that have no related correlation with the second blank.
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If you spot routines as keyword, then sporadically has no sense nor D.

Regards

How ploddingly becomes meaningful here if not sporadically or impetuously

How ploddingly becomes meaningful here if not sporadically or impetuously

The fact that artists do not have routines for their work is a myth but indeed is not true

They have habits (B) and these habits a predictable (ploddingly)

Hope this helps.

Regards

Everyone has routines that govern their work. The myth is that artists are somehow different, that they reject (i)________, but of course that’s not true: most artists work as the rest of us do, (ii) ________, day by day, according to their own customs.

The sentence begins by asserting that everyone has routines that govern their work.

It then states that it is a myth that the artists are somehow different and reject _________.

Clearly the word for the blank in the above sentence should be routine. Hence Choice B habit, is the correct answer.

After the colon, which further explicates what came before it, the sentence states "most artists work as the rest of us do, (ii) ________, day by day, according to their own customs."

If they work as the rest of us do, day by day, then they must be working according to routines. We can rule out sporadically which means occasionally or at irregular intervals, and impetuously which means "in a sudden way, without considering the results of your actions". Therefore, ploddingly, which means laboriously, is the best and only choice.
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The issue here with the word ploddingly, the google dictionary definition is :
1- slow-moving and unexciting.
A. (of a person) thorough and hard-working but lacking in "imagination or intelligence."

2- plod
A.walk doggedly and slowly with heavy steps.
B. work slowly and perseveringly at a dull task.

I perceive plod as someone who walks slowly and he is tired. So, that's why the confusion is happening.
The GRE Vocab. nuances is INSANE
Carcass

Key Word to be marked: CUSTOM = a traditional and widely accepted way of behaving or doing something that is specific to a particular society, place, or time.
So HABIT IS indicative here.

Second thing is based on Voca: i didn't know the meaning of PLODDINGLY.........but know the meaning of sporadic = not regular one......impetuously =acting or done quickly and without thought or care.

both of them not related to habit or custom


Hope it helps.