<span>The correct answer is letter A, disorders in individual genes are responsible for Down's syndrome.
This is a human genetic disorder that is associated with physical growth delays, characteristic facial features, and a mild to moderate intellectual disability. This is a condition in which the genes make a copy of the chromosome 21. </span>
I believe they are positioned Beneath one of the clavicles. Pacemaker is a small device that's placed in the chest or abdomen to help control abnormal heart rhythms. This device uses electrical pulses to prompt the heart to beat at a normal rate. Pacemakers are used to treat arrhythmias. Arrhythmias are problems with the rate or rhythm of heartbeat.
I meant to say energy is the answer to your question
At least 75% of the history of the earth
