Read the passage on crude mineral oil and answer the comprehension question: According to the passage, how does crude oil come out of the earth?

Introduction / Context:
This question is based on a reading comprehension passage about crude mineral oil. Such passages are common in competitive exams to test your ability to read carefully, identify key details, and distinguish between similar sounding options. The question asks specifically about the appearance and smell of crude oil as it comes out of the earth, which is explicitly described in the first lines of the passage.

Given Data / Assumptions:

• The passage states: "Crude mineral oil comes out of the earth as a thick brown or black liquid with a strong smell."
• The focus is on colour (brown or black), consistency (thick liquid), and smell (strong).
• Options modify these details slightly to create confusion.
• We assume that the student has read the passage exactly as given in the question.

Concept / Approach:
Reading comprehension questions require you to locate specific information and match it accurately. The best approach is to refer back to the relevant line in the passage and compare it word-for-word with the answer choices. Even small changes, such as "mild" instead of "strong" or "red brown" instead of "brown or black", are enough to make an option incorrect. Therefore, precision is crucial when selecting the answer.

Step-by-Step Solution:
Step 1: Identify the line in the passage that answers the question. It clearly says: "Crude mineral oil comes out of the earth as a thick brown or black liquid with a strong smell." Step 2: Break down the description into parts: "thick", "brown or black", "liquid", "with a strong smell". Step 3: Examine option A: "Thick brown or black liquid with mild smell." Only the last part "mild smell" is different from the passage, which says "strong smell". So this option is incorrect. Step 4: Examine option B: "Thick red brown liquid with strong smell." The colour "red brown" does not match "brown or black". So this is incorrect. Step 5: Examine option C: "Mixture of different colours." The passage does not mention a mixture of different colours; it mentions specifically brown or black. Step 6: Examine option D: "Thick brown or black liquid with a strong smell." This matches the passage exactly in all details.

Verification / Alternative check:
To verify, you can read the first two lines of the passage again. The description is clear and direct. There is no mention of "mild" smell, no mention of "red brown" colour, and no mention of many colours. The only difference between option D and the passage is the addition of the article "a" before "strong smell", which does not change the meaning. Therefore, option D is the only answer that faithfully reflects the text.

Why Other Options Are Wrong:

• Thick brown or black liquid with mild smell: Changes "strong smell" to "mild smell", which contradicts the passage.
• Thick red brown liquid with strong smell: Alters the colour description to "red brown", which is not stated in the passage.
• Mixture of different colours: Introduces the idea of multiple colours, which is not mentioned; the passage is specific about "brown or black".

Common Pitfalls:
Students often rush through options and pick the one that seems closest without checking every detail. Exam setters deliberately introduce small changes in adjectives or qualifiers, such as "mild" versus "strong", to test attentive reading. To avoid such mistakes, always cross-check each word in the option against the relevant sentence in the passage. Underlining key descriptive words while reading can also help you quickly verify answers later.

Final Answer:
According to the passage, crude oil comes out of the earth as a thick brown or black liquid with a strong smell.