Please select the eligibility criteria that correspond to the clinical trial below.
Title: A 2-year Longitudinal Study on the Structural and Optical Effects of Orthokeratology Treatment on Eye
Brief Summary: This is a two-year longitudinal study investigating the optical and structural effects of increased compression factor of orthokeratology lens on eyes and the corresponding effect on change in choroidal thickness and therefore myopic control.


Options:
A: Inclusion Criteria:

* 6 to 10 years old
* Myopia: between 0.50 D and 4.00 D in both eyes
* Astigmatism: \<1.50 D; ≤ 1.25 D for with-the-rule astigmatism (axes 180 ± 30); ≤ 0.50 D for astigmatism of other axes in both eyes
* Anisometropia: ≤ 1.50 D
* Symmetrical corneal topography with corneal toricity \<2.00 D in both eyes
* Agree for randomization

Exclusion Criteria:

* Contraindications for orthokeratology wear (e.g. limbus-to-limbus corneal cylinder and dislocated corneal apex)
* Any type of strabismus or amblyopia
* Myopic treatment (e.g. refractive surgery and progressive lens wear for myopic control) before and during the study period
* Rigid contact lenses (including orthokeratology lenses) experience
* Systemic condition which might affect refractive development (for example, Down syndrome, Marfan's syndrome)
* Ocular conditions which might affect the refractive error (for example, cataract, ptosis)
* Poor compliance for lens wear or follow-up
B: Inclusion Criteria:

1. The subject must be enrolled in the parent protocol for at least one year.
2. The subject's parent or legal guardian must read and sign the STATEMENT OF INFORMED CONSENT and the subject must read and sign the Child's Assent Form and be provided a copy of each form.
3. The subject must appear able and willing to adhere to the instructions set forth in this clinical protocol.

Exclusion Criteria:

1. Ocular or systemic allergies that may interfere with contact lens wear.
2. Systemic disease or autoimmune disease or use of medication (e.g. antihistamine), which may interfere with contact lens wear.
3. Clinically significant (grade 3 or 4) corneal edema, corneal vascularization, corneal staining or any other abnormality of the cornea, which may contraindicate contact lens wear.
4. Clinically significant (grade 3 or 4) tarsal abnormalities or bulbar injection that might interfere with contact lens wear.
5. Any ocular infection.
6. Any corneal distortion resulting from previous hard or rigid gas permeable contact lens wear.
7. Any infectious disease (e.g. hepatitis, tuberculosis) or an immunosuppressive disease (e.g. HIV)
8. Diabetes
9. Previous refractive surgery, orthokeratology, keratoconus, or other corneal irregularity in either eye. Rigid contact lens wearers cannot be enrolled in the study.
10. Strabismus.
11. Pupil or lid abnormality or infection in either eye
12. Central corneal scar in either eye
13. Aphakia in either eye
14. Contraindications to contact lens wear such as dry eye or history of prior unsuccessful contact lens wear.
15. History of participation in prior clinical trials aimed to control myopia progression, except for the parent trial
16. Surgically altered eyes, ocular infection of any type, ocular inflammation.
17. Anterior chamber angle grade 2 or narrower by Van Herrick method.
C: Inclusion Criteria:

* All the students in Grade 1

Exclusion Criteria:

* No
D: Inclusion Criteria:

* Grade of 1 to 5 in elementary schools and grade of 7 to 8 in secondary schools.

Exclusion Criteria:

* Visual defect or other eye diseases; wearing orthokeratology; refractive surgery history.

Answer: A