Which of the following are signs that a boy is going through puberty? a. growth of facial hair and longer finger nails b. voice gets deeper and growth of facial hair c. voice gets deeper and hair color changes d. shoulders broaden and skin darkens

 B.voice gets deeper and growth of facial hair

B. voice gets deeper and growth of facial hair

Puberty can be defined as physiological, morphological and anatomical changes that occur in a human body. It is a stage of growth which forms transition between childhood and adulthood. It starts in the age of 8- 12 years. It is caused by the release of the androgen, and testosterone hormones which brings changes. The changes like deepening of voice and growth of the facial hair are the examples of signs that develop in boys during puberty.

The biosphere relies on the other spheres & survival cuz the air needed the life processes , it relies on the hydrosphere for the water needed for the life processes , it relies on.the geosphere nutrients needed for life processes , it relies on the cryosphere to make a snowman :-)
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