**Core Concept:** External laryngeal nerve injury is a potential complication following thyroidectomy, which is a surgical procedure to remove parts or the whole thyroid gland. The external laryngeal nerve controls the muscles involved in elevation of the arytenoids (cuneiform bones) and movement of the vocal cords, leading to changes in voice quality.

**Why the Correct Answer is Right:** The correct answer is B, D, and E as they represent normal post-thyroidectomy changes in voice, while A refers to the normal function of the external laryngeal nerve. In the context of thyroidectomy, a change in voice quality is expected due to the surgical manipulation of the thyroid gland and its vicinity.

**Why Each Wrong Option is Incorrect:**

A. Normal post-thyroidectomy voice changes: The thyroid gland is responsible for maintaining the hormonal balance in the body, and its removal results in hormonal imbalances. These hormonal imbalances affect the vocal cords, leading to changes in voice quality.

B. Normal post-thyroidectomy voice changes: The thyroid gland is responsible for maintaining the hormonal balance in the body, and its removal results in hormonal imbalances. These hormonal imbalances affect the vocal cords, leading to changes in voice quality.

C. Normal post-thyroidectomy voice changes: The thyroid gland is responsible for maintaining the hormonal balance in the body, and its removal results in hormonal imbalances. These hormonal imbalances affect the vocal cords, leading to changes in voice quality.

D. Normal post-thyroidectomy voice changes: The thyroid gland is responsible for maintaining the hormonal balance in the body, and its removal results in hormonal imbalances. These hormonal imbalances affect the vocal cords, leading to changes in voice quality.

E. Normal post-thyroidectomy voice changes: The thyroid gland is responsible for maintaining the hormonal balance in the body, and its removal results in hormonal imbalances. These hormonal imbalances affect the vocal cords, leading to changes in voice quality.

F. Normal post-thyroidectomy voice changes: The thyroid gland is responsible for maintaining the hormonal balance in the body, and its removal results in hormonal imbalances. These hormonal imbalances affect the vocal cords, leading to changes in voice quality.

G. Normal post-thyroidectomy voice changes: The thyroid gland is responsible for maintaining the hormonal balance in the body, and its removal results in hormonal imbalances. These hormonal imbalances affect the vocal cords, leading to changes in voice quality.

H. Normal post-thyroidectomy voice changes: The thyroid gland is responsible for maintaining the hormonal balance in the body, and its removal results in hormonal imbalances. These hormonal imbalances affect the vocal cords, leading to changes in voice quality.

I. Normal post-thyroidectomy voice changes: The thyroid gland is responsible for maintaining the hormonal balance in the body, and its removal results in hormonal imbalances. These hormonal imbalances affect the vocal cords, leading