1. What is he wearing on his head?

-He is wearing a wig?

2. What is he wearing on his upper body?
- He is wearing a T-shirt.

3. What is she wering on her feet?
- She is wearing sandals.

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We can divide our body into three parts. After that we can ask the questions as in the above. Can you check the questions and answers? Do you have more appropriate questions for three parts in our body?

Your first and third questions are quite normal, but for the middle, I usually hear and use the following:

What is she wearing today:
-- She is wearing a new T-shirt and a pair of shorts.

What kind of shirt is he wearing?
-- He is wearing a dress shirt, but without a tie.

What is he wearing today?
-- He is wearing a pair of dress trousers, turtleneck shirt, and a sports coat.

The questions and answers provided are accurate based on the information given. However, if you want more appropriate questions for the three parts of the body, here are some suggestions:

1. What is he wearing on his head?
- He is wearing a cap/hat.

2. What is he wearing on his upper body?
- He is wearing a shirt/blouse.

3. What is she wearing on her feet?
- She is wearing sneakers/boots.