Correct Answer: 20, 5, 1, 3, 8, 5, 18

Solution : When alphabets are serially numbered →

Let's compare the given options –

Firs t o ption : 5, 18, 5, 8, 1, 3, 5

Here, alphabets of the given place value are → E, R, E, H, A, C, E

Second o ption: 20, 5, 1, 3, 8, 5, 18

Here, alphabets of the given place value are → T, E, A, C, H, E, R

Third option: 5, 1, 3, 5, 20, 8, 18

Here, alphabets of the given place value are → E, A, C, E, T, H, R

Fourth o ption: 18, 5, 3, 8, 1, 5, 20

Here, alphabets of the given place value are → R, E, C, H, A, E, T

So, by arranging the letters, only the second option has a meaningful word i.e. TEACHER.

Hence , the second option is correct.