What is the length of the M9 service pistol?

The M9 service pistol has a total length of 8.54 inches, which makes this the correct choice. This measurement includes the entire firearm, from the end of the pistol's muzzle to the rear of the grip. Understanding the dimensions of the M9 is important for tasks such as holstering, storage, and overall handling. Additionally, being knowledgeable about its specifications helps maintain proficiency with the weapon.

Other options provide different lengths that do not align with the accurate measurement of the M9, which is essential for proper identification and comprehension of the firearm's characteristics. Knowing the exact length is crucial for operational readiness and ensuring that all equipment and accessories, like holsters and sights, are compatible with the pistol.