Which of the following physical gestures is legislated as Sunnah for the caller of the Adhan but NOT for the Iqamah?

Adhan and Iqamah: Phrasing, Echoing, and Conduct

• Standing while facing the Qiblah.
• Placing the index fingers inside the ears.
• Turning the neck to the right and left.
• Speaking in a loud voice.