Answer:
The answers are CD, JS, and CT.
Explanation:
Even though CT is a diameter, it is still a chord because a diameter is a special chord: It's the longest chord of a circle, it has 3 collinear points, and it passes through the center of a circle.
The definition of "chord" is: a straight line segments whose endpoints both lie on the circle.
You might be wondering: how is JS a chord? Well, this is why.
Since this shape is 3-D, not 2-D, then the endpoints of a chord can be anywhere on the actual sphere, not inside it, and not outside of it. It this would be a 2-D shape, or a circle, then JS would not be a chord because its endpoints aren't on the actual circle. But since this shape is a sphere, JS is a chord. I hope I explained it fine. Sorry if it's confusing.
CD is a chord because both of its endpoints are on the sphere.
By the way, I did this assignment, and I got it wrong because I did only CD and CT, not CD, JS, and CT. But now I understand why I got it wrong, and I hope you understand, too! :)