Combination Question

Hi, This is T.Murat from Bangkok.

First, we should assume D & E as one person; call it K.

Then, we have A, B, C, and K to be seated in a row. That will be in 4! ways, 24 ways.

Lastly, focus back on D & E, they can seat in 2 different ways; DE  or ED, in all of these 24 ways.

That adds up to 24 x 2 = 48 different arrangements.

All the best.