The act of strengthening the muscles of the abdomen and torso is <u>core strengthening.
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Explanation:
The core is the central part of the body comprised of about 35 (major and minor) muscle groups which connect to the pelvis, spine and hip area. These can be broadly grouped as the abdominals, back extensors, hip, and lateral trunk muscle groups.  
The core area is the centre of gravity and stability for all bodily movements. 
Strength of core muscles is very important especially to athletes and sports persons. Weakness of core muscles leads to general body weakness and fatigue, muscle injuries like sprains, less endurance and power, back pain, and poor posture.  
Core strengthening exercises are done to train the core muscles and strengthen them and work in harmony for better body balance, stability, and movement. Core strengthening exercises include crunches, plank, L-sit, sit-ups, push-ups etc
 
        
             
        
        
        
B. Where the people recovering from drug abuse live together.
        
             
        
        
        
Answer:
"Certification" is a voluntary process by which a nongovernmental agency grants a time-limited recognition to an individual after verifying that he or she has met predetermined and standardized criteria. To become certified, an individual must meet eligibility requirements and pass an assessment.
Explanation:
The definition above is applied for healthcare field.
We can find different contents for the definition of Certification in dictionaries.
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Hope this answer can help you. Have a nice day!