Out of the four alternatives, choose the one which can be substituted for the given words/sentence: "Drug which causes people to sleep easily".

Introduction / Context:
This one-word substitution question checks your knowledge of specific vocabulary used in medical and general English. The phrase given is "Drug which causes people to sleep easily". You are required to find a single word that captures the idea of something that induces sleep. Such words often appear in medical contexts, articles about medicines, and advanced reading passages.

Given Data / Assumptions:

• Phrase: "Drug which causes people to sleep easily".
• Options: Poppy, Soporific, Beguile, Pedant.
• We assume the question refers to the general effect of a drug, not a specific plant or unrelated concept.

Concept / Approach:
The word "soporific" is used in English to describe something that causes sleep or has a strong tendency to make people drowsy, especially a drug or medicine. The other options are distractors: "Poppy" is a plant, "beguile" means to charm or deceive, and "pedant" refers to a person who is overly concerned with minor details or rules. To answer, we match the definition in the question with the technical term that directly describes a sleep-inducing substance.

Step-by-Step Solution:
Step 1: Focus on the key idea: a drug that makes people fall asleep easily. Step 2: Examine "Poppy". While poppy plants are linked to opium and some sleep-inducing substances, the word "poppy" itself refers to the plant, not specifically to a sleep-inducing drug. Step 3: Examine "Soporific". This adjective (and sometimes noun) means "tending to induce drowsiness or sleep". It is used precisely for sleep-causing agents. Step 4: Examine "Beguile". This means to charm, amuse or deceive someone, often by trickery, and has no connection to sleep-inducing effects. Step 5: Examine "Pedant". A pedant is a person who is excessively concerned with minor details and rules; again, it is not related to drugs or sleep. Step 6: Therefore, "Soporific" is the only word that matches the required meaning exactly.

Verification / Alternative check:
Dictionary definitions describe "soporific" as "causing or tending to cause sleep" or "marked by sleepiness". Typical usage includes phrases like "a soporific drug" or "a soporific lecture". In medical contexts, medicines prescribed for insomnia or to sedate a patient may be described as soporific. Replacing the phrase in the question with "soporific" gives "a soporific drug", which captures the intended meaning perfectly.

Why Other Options Are Wrong:

• Poppy: Refers to a type of plant; although some derivatives have sedative effects, the word itself does not specifically mean "drug that causes sleep".
• Beguile: Means to charm or deceive someone; unrelated to sleep induction.
• Pedant: Describes a person who is overly concerned with academic rules or details, not a type of drug.

Common Pitfalls:
Some students may be tempted by "Poppy" because they associate it with opium and sleep-inducing drugs. However, in one-word substitution questions, the exam expects the precise technical term that directly matches the definition given, which is "soporific". To do well in such questions, it is important to learn exact vocabulary meanings rather than rely on loose associations.

Final Answer:
The correct one-word substitute is Soporific.