In each of the following questions on idioms and phrases, choose the alternative which best expresses the meaning of the idiom Pros and Cons.

Introduction / Context:
Idioms and fixed phrases form an important part of English vocabulary, and understanding them is essential for doing well in competitive exams. The expression Pros and Cons is frequently used in discussions, debates, and written arguments. It does not literally refer to professional people and criminals, even though the words pros and cons can have those meanings in other contexts. Instead, it has a fixed idiomatic sense related to evaluating both sides of a question.

Given Data / Assumptions:

• Idiom: Pros and Cons.
• Options: Professionals, Con artists, Professionals and con artists, Advantages and disadvantages.
• We must select the option that correctly conveys the established idiomatic meaning.
• We assume exam level knowledge of common discussion phrases.

Concept / Approach:
In idiomatic usage, Pros and Cons means the positive and negative points of a suggestion, plan, or situation. The word pros refers to arguments in favour, and cons refers to arguments against. Together, they invite a balanced evaluation. The option Advantages and disadvantages summarises this meaning accurately. The other options play on the literal sense of pro as professional and con as criminal, which is not relevant in this idiom. Recognising when words are used as parts of idioms rather than literal vocabulary items is crucial here.

Step-by-Step Solution:
Step 1: Recall that when people say Let us weigh the pros and cons, they mean Let us consider the good points and bad points. Step 2: Examine option Advantages and disadvantages, which directly expresses the idea of positive and negative aspects. Step 3: Examine Professionals, which refers to people with expert skills and has nothing to do with negative points or arguments against something. Step 4: Examine Con artists, which refers to criminals who cheat others, again unrelated to balancing arguments for and against. Step 5: Examine Professionals and con artists, which combines the two literal senses but still does not capture the idea of evaluating both sides of a proposal. Step 6: Recognise that only Advantages and disadvantages matches the idiomatic meaning. Step 7: Conclude that the correct interpretation of Pros and Cons is Advantages and disadvantages.

Verification / Alternative check:
Consider a sentence from a meeting: Before buying this new machine, we should discuss the pros and cons. If we substitute Advantages and disadvantages, the sentence remains natural and clear: we should discuss the advantages and disadvantages. Using Professionals or Con artists would make the sentence nonsensical. Dictionaries and phrase books also define Pros and Cons as arguments for and against or the good and bad aspects of something. This confirms that the fourth option is correct.

Why Other Options Are Wrong:
Professionals is wrong because pro in this idiom does not refer to professional, but to pro as the Latin prefix meaning for. Con artists is wrong because con in this context does not stand for confidence trickster but for the Latin prefix meaning against. Professionals and con artists is clever but incorrect, as it mixes up unrelated meanings and completely misses the idiomatic sense of the phrase. None of these options reflect the balanced evaluation implied by Pros and Cons.

Common Pitfalls:
A few learners may overthink and look for clever connections between words rather than relying on familiar idiomatic usage. They may also be misled by the modern use of pro and con in other contexts. To avoid this, it is important to memorise common idioms like Pros and Cons as fixed units with fixed meanings. When an expression is often heard as a set phrase in decision making discussions, the safest interpretation is usually that idiomatic one rather than any creative literal interpretation.

Final Answer:
The idiom Pros and Cons means Advantages and disadvantages.