Is it required to claim an eligible tax dependent?

My daughter is 26 and no income last year, so she is still eligible to be my tax dependent for 2021. However, what I would like to know is if it is mandatory for me to claim her as a dependent?

 

The reason why I am asking is when I submitted her health care application one month ago, I thought my daughter is no longer qualified as my tax dependent because of her age. However, when I was using Turbo tax to prepare the tax return, I noticed she is still eligible to be my tax dependent since she doesn't have any income.

 

Thank you,

Charles