Steps to Create an Original Challenge
Select the Questions tab on Track Contents Manager.
On the right side, click + Add Question

For Question Type, choose Fill in Blank.

Enter a Title and compose the Question.
Add one or more answers, then click OK

※ If you add or update a Question that belongs to a Challenge already included in an Exam, be sure to update that Challenge to its latest version.
See: How to Replace a Challenge with Its Latest Version
The default placeholder syntax is ${}
When you click Add Blank, ${ANSWER} appears.
You can register the correct answer by replacing ANSWER inside ${}
Example with multiple blanks in one sentence:
The three primary colors of light are ${red}, ${green}, and ${blue}.
The examinee must fill in all three blanks correctly to earn points.