The given word is "difficult" and we need to find a synonym for it.
Answer: C. hard
Explanation:
Here is the explanation of why "hard" is the correct synonym for "difficult":
1. "Difficult" and "hard" have similar meanings, both indicating that something is not easy to do or understand.
2. "Soft" is the opposite of "difficult" and does not have the same meaning.
3. "Easy" is the opposite of "difficult" and does not have the same meaning.
4. "Old" is unrelated to the word "difficult" and does not have the same meaning.
In conclusion, out of the given options, C. hard is the correct synonym for the word "difficult".

Understanding the Word "Difficult"
To grasp why "hard" is the correct synonym for "difficult," let's break down the meanings of these words.
Definition of "Difficult"
- "Difficult" refers to something that requires a lot of effort, skill, or determination to accomplish.
- It often implies a challenge that is not easy to overcome.
Definition of "Hard"
- "Hard" can describe something that is not easy to do, understand, or deal with.
- It aligns closely with the notion of difficulty, as both words convey a sense of challenge.
Why "Hard" is the Correct Synonym
- Both "difficult" and "hard" suggest a level of challenge that makes tasks or situations less straightforward.
- They can be used interchangeably in many contexts, such as:
- A hard math problem is a difficult math problem.
- A hard task is a difficult task.
Other Options Explained
- Soft: This word refers to a texture or temperament that is gentle and not hard, making it the opposite of "difficult."
- Easy: This term means something that can be done without much effort, clearly contrasting with "difficult."
- Old: This word pertains to age and has no relation to the concept of difficulty.
Conclusion
In summary, the correct answer is option 'C' (hard) because it shares a synonymous relationship with "difficult," both indicating a challenge that requires effort to overcome. Understanding these definitions can help in language comprehension and vocabulary building.