# Single-Select Dropdown
The single-select dropdown labeling tool allows you to ask labelers close-ended questions with one right answer.
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The Single-Select Dropdown tool is supported across the Audio, Image, Video, DICOM, Medical, PDF, Text, LLM, and Markdown labeling editors.
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## The Single-Select Dropdown Labeling Tool in Ango Hub
### How to add a Single-Select Dropdown tool to your project
From the project’s *Settings* tab, enter the *Label Set* section.
Click on *Add Category*. From the list that appears, click on *Single-Select Dropdown*.
A new row will appear named *Single-Select Dropdown*. Click on it to expand it.
Give your single-select dropdown tool a title and description. From the *Options* text box, you can enter the answers. Press *Enter* after entering each one.
Enable the *Required* toggle if you want to force labelers to answer it. When the toggle is disabled, labelers will be able to save and move to the next asset without answering this question.
If you would like to ask labelers further questions, for example, if you want to show a Text tool when labelers answer *Other*, click on *Add Classification* and add a further question. [More on nested questions here](https://docs.imerit.net/labeling/labeling-tools/tools/nested-classifications).
### Differences between Radio and Single-Select Dropdown
The tool is functionally identical to the [Radio tool](https://docs.imerit.net/labeling/labeling-tools/classification-tools/radio), with the main difference being visual.
The major benefit of the radio tool over the dropdown tool is that it can be answered by a labeler with a single click, instead of the two required for dropdowns. The downside is that it cannot easily display large numbers of items. Here’s an example of how to ideally use radios and dropdowns:
When the number of possible answers is limited, we recommend choosing the Radio tool. For questions with a significant amount of more answers, the dropdown tool is preferable.
### Differences between the Single and Multi-Select Dropdown tools
In single-select dropdowns, labelers can only select one answer. In multi-select dropdowns, labelers can select more than one.