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What is In a patient of Class II div 1, which of the following features is present? and explain in detail?
Skeletal class I: An orthognathic face with the following important features:

Straight profile
Normal ANB angle: 2° ± 2
Normal facial angle (downs): 82–95° (mean 87.3°)
Angle of convexity (downs): +10 to −8.5° (mean 0°).

Skeletal class II: A retrognathic face that may be due to a prognathic maxilla or retrognathic mandible. Important features are:

Convex profile
Increased ANB angle
Reduced facial angle
Increased angle of convexity
Severe backward rotation of the mandible may also be present.

Skeletal class III: A prognathic face at chin that may be due to a prognathic mandible or retrognathic maxilla. Possible significant features are:

Concave profile
Prominent chin
Decreased ANB angle
Increased facial angle
Reduced angle of convexity.

Reference: Orthodontics: Diagnosis and Management of Malocclusion and Dentofacial Deformities 3rd O P Kharbanda, pdf no 337