In the following question, out of the given four alternatives, select the one which best expresses the meaning of the given word "Abettor".

Introduction / Context:
This vocabulary question focuses on the legal or semi-legal term "abettor". This word is often used in law, crime reports, and discussions of wrongdoing. Understanding it is important for interpreting legal language, news articles, and examination passages on crime and justice.

Given Data / Assumptions:

The target word is "abettor".
We assume the standard meaning: a person who encourages, assists, or helps another person to commit a crime or wrongdoing.
The options are accomplice, adversary, careless, indolent, and spectator.

Concept / Approach:
An "abettor" (also spelled "abettor" in some jurisdictions) is someone who aids and encourages the commission of a crime. The closest everyday synonym is "accomplice", which refers to a person who helps another to commit a crime or who participates in it. Adversary is an opponent, careless means not taking sufficient care, indolent means lazy, and spectator means one who only watches. Thus, "accomplice" directly matches the role described by "abettor".

Step-by-Step Solution:
Step 1: Restate "abettor" as "one who aids or encourages someone in committing an offence". Step 2: Option A "Accomplice" is defined as someone who helps another person to commit a crime. Step 3: Option B "Adversary" refers to an enemy or opponent, not a helper in wrongdoing. Step 4: Option C "Careless" is an adjective describing lack of attention, not a person who helps in a crime. Step 5: Option D "Indolent" means lazy and again does not necessarily involve crime or assistance. Step 6: Option E "Spectator" describes someone who only watches an event without taking part, whereas an abettor is actively involved in aiding.

Verification / Alternative check:
Consider the phrase "an abettor to murder" and "an accomplice to murder". Both suggest someone who helped the main offender. If we replaced "abettor" with "adversary" or "spectator", the meaning would change drastically and no longer indicate helping the crime. Legal phrases like "aid and abet" further confirm that an abettor is someone who supports or assists the principal offender. This aligns perfectly with "accomplice".

Why Other Options Are Wrong:
Option B Adversary is a person who actively opposes or is hostile to someone; it is nearly the opposite of a helper.
Option C Careless is merely a description of someone's attitude; it does not describe a role in a crime.
Option D Indolent refers to laziness and is unrelated to legal participation in wrongdoing.
Option E Spectator suggests passive observation, whereas an abettor takes active supportive steps in the offence.

Common Pitfalls:
Some test takers may confuse "abettor" with "adversary" because both words can appear in legal contexts, but their roles are very different. Remember that "to abet" means "to encourage or assist" in wrongdoing, while an adversary is an opponent. The phrase "aid and abet" is a good memory aid: both verbs describe helping, not opposing. Linking "abettor" with "accomplice" in your memory will ensure you choose correctly in exams.

Final Answer:
The word that best expresses the meaning of "Abettor" is "Accomplice".