取引先からの依頼に対して:「___いたしました。明日までに対応いたします」
Q. Which word is the appropriate business acknowledgment to a client?
Translation
"Understood. We will take care of it by tomorrow."
Explanation
承知いたしました is the humble, client-appropriate acknowledgment. 了解しました is common between colleagues but is widely considered too casual toward clients or superiors; 納得 means being personally convinced, which misses the point.