Which of the following is not a factor in balanced occlusion?
Definition: The bilateral, simultaneous, anterior and posterior occlusal contact of teeth in centric and eccentric positions (GPT8).
Lever balance: This is the relation of the tooth to its base of support. It is important when a bolus of food is placed in between the teeth on one side and a space exists on the opposite side . It is enhanced by the following:

Placing the teeth such that resultant direction of force on the chewing side is on the crest or slightly lingual.
Placing the teeth close to the ridge.
Denture base covering as wide an area as possible.
Reducing the buccolingual width of the teeth.

Key Concept:
Wider the ridge and narrower the teeth buccolingually, greater will be the balance.
Ref: Textbook of prosthodontics V Rangarajan Ed. 2nd
More lingual the teeth are placed in relation to ridge, greater the balance
More buccal the teeth are placed in relation to ridge, poorer the balance
Wider the ridge and wider the teeth buccolingually, greater the balance
More centred is the force of occlusion anteroposteriorly, greater is stability of base