Select the most appropriate synonym of the given word. Deficient

The most appropriate synonym of the word "deficient" is incomplete. This is because "deficient" means "lacking something necessary for completeness", while "incomplete" means "not having all the necessary parts or elements". The other words do not have the same meaning as "deficient".

• Sleek means "smooth and elegant in appearance".
• Whole means "complete and not damaged or missing any parts".
• Integral means "essential or necessary to the completeness or functioning of something".