In the following question, out of the four alternatives, choose the word which best expresses the meaning of the given word OMINOUS.

Introduction / Context:
This is a vocabulary question that tests your knowledge of synonyms. The given word is ominous, which appears frequently in newspapers, novels and exam passages. Selecting the correct synonym requires that you recall or infer the typical situations in which ominous is used, and then choose the option that matches that meaning as closely as possible.

Given Data / Assumptions:
- Target word: OMINOUS. - Options: OFFICIOUS, PLEASANT, CONVENIENT, THREATENING. - Exactly one option should closely match the meaning of ominous.

Concept / Approach:
The word ominous is associated with bad signs, dark hints and the feeling that something harmful or unpleasant is about to happen. Headlines may speak of ominous clouds before a storm or ominous signs in the economy before a crisis. Therefore, the correct synonym should carry a sense of danger, warning, or threat. Words that suggest comfort, helpfulness or ease will not match this negative predictive meaning. By focusing on such context clues, we can narrow down the choices effectively.

Step-by-Step Solution:
Step 1: Recall that ominous is linked to omens and usually refers to a sign that something bad will happen. Step 2: Consider OFFICIOUS. Officious refers to a person who is too eager to offer unwanted help or advice. It does not carry the sense of danger or bad omen. Step 3: Consider PLEASANT. Pleasant means enjoyable or agreeable, which is the opposite of the dark and worrying feeling created by something ominous. Step 4: Consider CONVENIENT. Convenient means handy or easy to use or do, which is again neutral or positive, not threatening. Step 5: Consider THREATENING. Threatening means showing a threat, giving the impression that something bad or harmful is likely to happen. This aligns very closely with ominous.

Verification / Alternative check:
You can verify the choice by placing each option in a typical sentence. For example, ominous clouds gathered over the city can be rewritten as threatening clouds gathered over the city without changing the meaning. However, pleasant clouds or convenient clouds would sound odd, and officious clouds would be meaningless. Similarly, ominous silence can be restated as threatening silence, but not as convenient or pleasant silence. This consistency across contexts confirms that threatening is the best synonym.

Why Other Options Are Wrong:
Officious is wrong because it relates to overhelpful or interfering behaviour, not to predictions of danger. Pleasant is wrong because it conveys a positive and enjoyable feeling, the opposite of the negative mood created by ominous. Convenient is wrong because it relates to ease or suitability and has no connection with bad omens or danger.

Common Pitfalls:
Some candidates may guess based on sound, because ominous somewhat resembles words like anonymous or unanimous, but this is misleading. Others may be unsure about officious and pick it simply because it looks formal. To avoid such errors, focus on meaning and remember typical collocations you have seen in reading. Words like ominous sign, ominous tone and ominous silence always indicate something bad is coming, so the memory of these phrases should automatically point you toward threatening as the correct choice.

Final Answer:
The word that best expresses the meaning of OMINOUS is THREATENING.