Wolverine is considered the most biologically realistic X-Man due to his accelerated healing and the plausibility of his adamantium skeleton. Beast follows closely, as his traits resemble those of various mammals, making genetic alteration a conceivable explanation. Rogue's original powers, linked to a super-evolved parasite, also appear somewhat realistic. Other characters like Longshot and Angel present challenges in terms of biological feasibility, with their powers being less grounded in reality. Overall, discussions highlight that while some powers may seem achievable through genetic engineering, others remain far-fetched and lack physical explanations.