How to simply write multiple comparisons using || with Ruby on Rails

Question

I want to write the conditions as such, but it's too long. How can I make it more simple?

if A
  ~~~
elsif B == b || B == c || B == d || B == e   <-- This part is too long.
  ~~~
else
  ~~~
end 

I thought it could be written as below, but it gave me an error, when I tried it on rails console.

elsif B == (b || c || d || e)

Answer 1

if B == b || B == c || B == d || B == e

can be written as

if [b, c, d, e].include?(B)