Which of the following radiation is most detrimental to human being?

Gamma rays ($\gamma \text{-rays}$) are highly energetic electromagnetic radiations with the greatest penetrating ability compared to alpha ($\alpha$) and beta ($\beta$) particles. While alpha particles are highly ionizing internally, external exposure to $\gamma \text{-rays}$ can easily penetrate deeply into human tissues, causing severe cellular and DNA damage throughout the body.