Fill in the blank with the most appropriate word.

He was born in a business family and has a natural aptitude ______ business.

for

He was born in a business family and has a natural aptitude for business.

Explanation:

• For: This is the correct preposition to use in this context. "Aptitude for" is the idiomatic expression to indicate someone's natural skill or inclination in a particular field.

• To: While "aptitude to" might be used in some contexts, it's not as commonly used as "aptitude for." "To" doesn't convey the same meaning of a natural affinity or skill in this case.

• At: "Aptitude at" is not the appropriate usage. We usually say "aptitude for" when referring to someone's natural talent in a certain area.

• On: "Aptitude on" is not a common expression and doesn't convey the intended meaning.