In the following passage about the value of books, choose the most appropriate word to complete the blank: So we should _____ only good books and read them.

Introduction / Context:
This question belongs to a passage that praises books as our friends and guides. The passage explains that books help us learn and find answers and then advises that we should read as many books as possible, but that not all books are good. Therefore, we should do something only with good books. The blank requires a verb that expresses the action of carefully selecting those books that are worth reading. Understanding the overall message of the passage helps to identify the correct word.

Given Data / Assumptions:
- The relevant lines are: We should read as many books as we can. But all books are not good. So we should _____ only good books and read them. - Options provided are remove, looking, steel and choose. - The passage emphasises that books are our real friends and guides. - The writer wants to instruct readers on how to handle the fact that some books are not good.

Concept / Approach:
We look for a verb that collocates naturally with only good books and with the idea of making a conscious decision. Among the options, choose clearly expresses the idea of selecting something from among many. Remove means take away, looking is a present participle and does not fit directly after should, and steel is a different verb meaning to harden yourself mentally. The correct collocation is choose only good books, which is a common way of advising people to be selective in reading.

Step-by-Step Solution:
Step 1: Insert choose in the sentence: So we should choose only good books and read them. This sounds natural and matches the intended advice. Step 2: Test remove. So we should remove only good books and read them is logically wrong, because we do not remove the good ones, we pick them up to read. Step 3: Test looking. So we should looking only good books and read them is grammatically incorrect, since should must be followed by the base form of the verb, not a continuous form. Step 4: Test steel. So we should steel only good books and read them does not make sense, because steel is not used with books in this way. Step 5: Conclude that choose is the only verb that is both grammatically correct and conceptually appropriate.

Verification / Alternative check:
We can further verify by thinking about how teachers and authors often advise students. They frequently say choose good books, select good reading material, or pick only good books. This is exactly the advice the passage is giving. The presence of only emphasises that from the large number of available books, we must select a smaller subset that are good in content and quality. Therefore, choose is perfectly aligned with the message.

Why Other Options Are Wrong:
Option A: Remove suggests taking something away or eliminating it. It would make sense to remove bad books, not good ones, so it contradicts the meaning. Option B: Looking cannot follow should without to and does not fit with only good books as an object, so it fails grammatically. Option C: Steel is not used for selecting books and therefore does not fit semantically in this sentence.

Common Pitfalls:
Sometimes students focus only on whether a word is grammatically possible after should and overlook whether it makes sense in the context. Another pitfall is to read quickly and miss the word only, which signals selection. Paying careful attention to the entire sentence, including words like only, helps you see that the intended action is to make a selection, which leads directly to choose as the best option.

Final Answer:
The verb that best completes the blank is choose, so option D is correct.