Explanation:

Introduction:
In this question, we are asked to identify the correct answer among the given options a), b), c), and d). The correct answer is option 'D', which means that all of the options are correct. Let's understand the meaning and usage of each of these options to further clarify why all of them are correct.

Options:

a) Otherwise:
- Meaning: 'Otherwise' is an adverb that is used to introduce an alternative or contrasting situation.
- Usage: It is used to indicate what will happen if a certain condition is not met or if an expected outcome does not occur.
- Example: "I need to finish my homework; otherwise, I won't be able to go out with my friends."

b) Therefore:
- Meaning: 'Therefore' is an adverb that is used to indicate a conclusion or result based on the information or evidence provided.
- Usage: It is used to show cause and effect or to draw a logical inference from the facts presented.
- Example: "The weather forecast predicts heavy rain; therefore, we should carry umbrellas."

c) Hence:
- Meaning: 'Hence' is an adverb that is used to show a cause-and-effect relationship or to indicate the reason or motive behind something.
- Usage: It is used to present a logical consequence or inference.
- Example: "She failed to submit her assignment on time; hence, she received a lower grade."

d) All:
- Meaning: 'All' refers to the collective or complete set of given options.
- Usage: It is used to indicate that every option mentioned is correct or valid.
- Example: "In this question, all of the given options are correct."

Conclusion:
In conclusion, the correct answer is option 'D' because all of the given options (a), b), c)) are correct. Each option has a distinct meaning and usage, and they can be used in different contexts to convey specific relationships or conclusions.