Question

$DEF,D_{3}E{F}_2,D{E}_2{F}_2,$ ______ $D_2{E}_2{F}_3$

• A. $DE{F}_3$
• B. $D_{3}E{F}_3$
• C. $D_2{E}_{3}F$
• D. $D_2{E}_2{F}_2$

Answer 1

The correct option is D $D_2{E}_2{F}_2$

In this series, the letters remain the same: $DEF$.

The subscript numbers follow this series:

$111,112,122,222,223,233,333,...$