Please assess the completion status of the following clinical trial:

Trial Title: Impact of Challenging Engagement on Cognition in Older Adults

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: PREVENTION
- Time Perspective: None
- Masking: NONE
- Phase: None
- Number of Arms: 3.0

Eligibility Criteria:
Inclusion Criteria:~* Participants must be adults at least 60 years old.~* At least 35 percent of participants will be men, and at least 15 percent will be minorities.~* 10th grade education or higher is required~* Fluent in English~* Alzheimer's Disease Assessment Scale-Cognitive (ADAS-COG) score of zero (a perfect score).~* A score of 18 or higher on the Barthel Index of Daily Functioning.~* Right-handed for magnetic resonance imaging (MRI) scanning.~Exclusion Criteria:~* Telephone Interview for Cognitive Status (TICS) lower than 25~* Montreal Cognitive Assessment (MOCA) score lower than 26~* Depression based on Center for Epidemiologic Studies Depression Scale (CESD) screening (a score of 27 or greater)~* Major psychiatric or neurological disorder~* Chemotherapy presently or in past year~* Coronary bypass presently or in past year~* History of major substance abuse~* History of central nervous system disease or brain injury~* Corrected vision poorer than 20/40 on Snellen Eye Chart after correction~* Recreational drug use in past six months~* Conditions which would contra-indicate MRI: Prior surgeries and/or implant of pacemakers, pacemaker wires, artificial heart valve, brain aneurysm surgery, middle ear implant, non-removable hearing aid or jewelry, braces or extensive dental work, cataract surgery or lens implant, implanted mechanical or electrical device, artificial limb or joint; foreign metallic objects in the body such as bullets, ball-bullets or ball bearings (BB's), shrapnel, or metalwork fragments; pregnancy, vertigo, claustrophobia, left handedness, Body Mass Index (BMI) greater than 35, uncontrollable shaking, or inability to lie still for one hour.~* More than minimal experience with photography during the last 12 years~* Work at a structured job/volunteer more than 10 hours per week~* Computer experience that involves more than internet surfing and email~* Use of electronic devices to shop, pay bills, bank, and perform other higher-order functions~* Extensive experience with digital photography or post processing photo programs

- Gender: ALL
- Minimum Age: 60 Years
- Maximum Age: None
- Healthy Volunteers: t

Study Arms:
- High-Demand Photography (Type: EXPERIMENTAL): A structured, high-demand photography course targeting 210 hours of engagement over 16 weeks.
- Moderate-Demand Photography (Type: ACTIVE_COMPARATOR): A structured, moderate-demand photography course targeting 210 hours of engagement over 16 weeks.
- At-Home Engagement Group (Type: PLACEBO_COMPARATOR): Participation, alone at home, in tasks that are relatively low in intellectual engagement.

Based on this trial design, predict the completion outcome and termination type (if applicable).