Can you give me proper word?

The following is from a Korean scholarastic aptitude test.

Would you try this?

The question is to choose the number of word  which is not proper.

1. 다음 그림을 바탕으로 한 글의 흐름으로 보아, 밑줄 친 단어의 쓰임이 적절하지 않은 것은? [3점]

If you connect a primitive digital camera to your PC and aim it at a happy face, your computer might perceive the image as it appears on the right-hand side of the given drawing. The digitized image of the face is ①rough because the computer thinks in terms of ones and zeros and makes all-or-nothing approximations. This will, in some cases, ②enhance subtle information about light versus dark differences, hence the ③lack of detail in the eyes and mouth, and in other cases ④exaggerate such differences, as shown in the edges of what should be a ⑤smooth, gradually curving face.

Thanks for reading.

The answer is #2 enhance.

What I want to know is if #2 is not proper, what word is possible?

Thanks.

"The digitized image of the face is rough because the computer thinks in terms of ones and zeros and makes all-or-nothing approximations. This will, in some cases, enhance subtle information about light versus dark differences, hence the lack of detail in the eyes and mouth."

I don't fully understand what this is actually saying, but "enhance subtle information about light versus dark differences, hence the lack of detail...", if subtle information is 'enhanced', it doesn't sound right that it would lead to a 'lack' of detail?  I'd have thought, enhanced would result in more detail?

Therefore, you could replace 'enhance' with 'affect' or 'reduce'

Grammar Geek wrote:

I think "ignore" might work. It can't see the subtle difference - it's all black or it's all white, so if a spot it's looking at has both, it has to make a decision about whether to go all black or all white. Other choices: overlook, minimze...

Thanks all of you.

Clive, Tidus, Grammer Geek.

I think Tidus' reply is most logical.

Here's what I thought.

In the following part, "enhance subtle information about light versus dark differences," ENHANCE contradicts LACK in "the lack of detail."

Since "enhance subtle information about light versus dark differences" means that the image becomes more clear, "the lack of detail" conflicts with "enhance subtle information about light versus dark differences."

In the given drawing 'the lack of detail' makes sense, so 'enhance' is wrong. And this is Tidus' point.

Thanks all of  you. Thanks.