The Next Letter…but Harder

Riddle: What letter comes next? A, B, C, D, _

Answer: It's not E; it's F, because if you put it on the line without removing the line, THEN you'll get an E.

Source: https://www.riddles.com/11452

What letter comes next? A, B, C, D, _ — The Next Letter…but Harder by Gabriella Simonetti v1.

Riddle: What letter comes next? A, B, C, D, _ Answer: It's not E; it's F, because if you put it on the line without removing the line, THEN you'll get an E. — by Gabriella Simonetti v2.