Final answer:
A soldier does not have an option to not take an APFT based on age; APFT requirements cease upon retirement or separation. The APFT has been replaced by the ACFT since 2020. Policies and exceptions may vary, including for medical profiles or as determined by superiors.
Step-by-step explanation:
The question asked pertains to the age at which a soldier has the option to not take the Army Physical Fitness Test (APFT). Generally, there is not a specific age at which a soldier can opt out of the APFT; rather, the requirement to take the APFT ends upon retirement or separation from service. However, it's important to note that the APFT has been replaced by the Army Combat Fitness Test (ACFT) as of 2020. Additionally, policies regarding physical fitness assessments can vary and exceptions or modifications may be made for medical profiles or as determined by commanding officers. There could be differences in such policies between different branches of the military and these could change over time.
As for the provided reference text about the Military Service Act stating that all males between eighteen and forty-five are eligible for compulsory military service, there are exemptions mentioned that don't relate to the APFT or age-based exemption from the physical fitness test, but to service in general. The exemptions include conscientious objectors, essential war occupations, special qualifications, and cases of special hardship. The effective date mentioned, October 12, does not correlate directly to the APFT or age-related exemptions.