Of the following traits which one is acquired not inherited

Eye shape
Fingernail length
Skin tone
Number and presence of dimples

Eye shape- This trait is generally inherited, as it is determined by the shape and structure of the eye muscles and tissues, which are determined by genetics.

Fingernail length- This trait is mainly acquired, as it is influenced by factors such as personal grooming habits, nail care, and external factors like accidents or injuries.

Skin tone- This trait is mainly inherited and determined by the amount of melanin in the skin, which is influenced by genetics.

Number and presence of dimples- This trait is primarily inherited, as it is caused by a variation in the genes that affect the development of facial muscles and skin.