Which of the following  is not included in Class I cavity preparation?
All preparations required to treat pit-and-fissure caries are termed Class I preparations.
These include preparations on

Occlusal surfaces of premolars and molars.
Occlusal two thirds of the facial and lingual surfaces of molars, and
The lingual surfaces of maxillary incisors.

Preparations required to correct caries lesions that develop in the proximal surfaces of posterior teeth are termed Class II preparations.
Preparations required to correct caries lesions or other defects that develop in the gingival third of the facial or lingual surfaces of all teeth are termed Class V preparations.
Preparations required to correct caries lesions or other defects that develop in the incisal edges of anterior teeth or the occlusal cusp tips of posterior teeth are termed Class VI preparations.
Reference: Sturdevant operative dentistry 7th EDITION page no.269
On occlusal surfaces of premolars and molars
On occlusal two thirds of the facial and lingual surfaces of molars
On the lingual surfaces of maxillary incisors
On occlusal cusp tips of posterior teeth