Based on the review of the provided `task.json` and `README.md` files, here are the identified issues:

### Issue 1
**Issue**: Inconsistency in JSON property `append_choices_to_input`
**Evidence**: In the `task.json` file:
```json
"append_choices_to_input": "false",
"append_choices_to_input": true,
```
**Description**: The property `append_choices_to_input` is duplicated with conflicting values (`"false"` as a string and `true` as a boolean). This can lead to confusion or errors in interpreting the dataset's structure or intended use.

### Issue 2
**Issue**: Missing standard JSON property conventions
**Evidence**: In the `task.json` file:
```json
"preferred_score": "multiple_choice_grade",
"metrics": ["multiple_choice_grade"]
```
**Description**: The property `preferred_score` is used but not typically standard in JSON schema for tasks; usually, `metric` or `evaluation_metric` might be used. This could lead to confusion about the dataset's evaluation procedures.

These issues suggest the need for a clearer specification and consistency in the dataset's documentation and structural formatting to ensure accurate usage and understanding of its intended purposes.