To add a matrix dropdown question in my survey:

1. Click Matrix Dropdown in the question types listed on the left pane. You can also drag and drop the question type to the builder. 
   
   
   
2. In the Question box, type your question. 
   
1. If you want to mark the question mandatory, select the Make this question mandatory checkbox.
   
2. If you want to make changes to the default Error message text that displays, edit the content in the text box.
   
3. If you want to pipe in custom variables or variables from previous questions and customize the follow up questions, click the arrow next to Insert Variable right above the Question box, and select the variable you want to use from the list. Read more on Piping.
   
4. In the Required number of rows dropdown list, select the number of rows you want to keep as mandatory. This can be in the form of at least, at most, exactly or in between. At least one row must be selected. If you want the respondents to answer all rows in the matrix, then select All. This option appears only if the  Make this question mandatory checkbox is selected.
   
5. In addition to the number of rows you selected, In the Required number of columns per row dropdown list, select the number (of columns) to keep as mandatory for the respondent to pick. This can be in the form of at least, at most, exactly or in between. The number of columns required should be lesser than the total number of columns. These two options appear only if the Answer mandatory for this question checkbox is selected.
   
3. In the Answer section, you need to add choices in the following sections:
   
1. In the Row labels boxes, type in the names for the rows. 
   
   
   
2. In the Column labels  boxes, type in the names for the columns.
   
3. In the Column labels  section, click  to provide the dropdown choices.
   
4. In the box that appears, type in each dropdown choice on a separate line. 
   
   
   
5. When you are done typing in the dropdown choices, Click Save. 
   
6. To go back and add a few more choices, click Cancel. 
   
4. Click + to add more boxes, and click X to delete choices.
   
5. To learn what else you can do with the question, click Advanced options. You can perform the following actions:​
   
1. To add a comments box, select Add 'Comments' field. If you want to change the name of the field, in the Comments field label box, type in the new field name.
   
2. Question hint is used to add hints to your question and help your respondents get a clear idea on what your questions are all about. This feature is optional and is available only for certain types of questions. 
   
   
   
6. Click Save.
   
7. To discard the changes, click Cancel.