What is a leading question? Federal Rule of Evidence 611(c)

Following up from the unpublished Fourth Circuit opinion earlier this week, the court addresses what is a leading question and if it is allowed:

UNITED STATES OF AMERICA, Plaintiff ­ Appellee, v. ERIC ANTONIO MEJIA-RAMOS, a/k/a Flaco, Defendant - Appellant. UNITED STATES OF AMERICA, Plaintiff ­ Appellee,, No. 17-4030, 2019 WL 6698120, (4th Cir. Dec. 9, 2019)