The answer is most likely:
A. Lower anxiety
Studies have shown that unconditional love actually gives a child a sense of security knowing that they are loved no matter what they do. (Duke University Medical School, 2010) They become less fearful to do new things even if they fail. Studies also show that they become more resilient, because unconditional love creates a stronger bond between parent and child. They are more resilient to risky behaviors as they grow old because they always want to please their parent/s.
Dangerous conditions influencing sport injuries include all answers which you've mentioned (overuse, overexertion, and incorrect technique). It doesn't, however, include practicing and drills - d.
Practicing and drills is the thing which would help us become more profficient at a certain task and eventually sport through it.
Answer: playing singles tennis or a bike on a hilly surface
Explanation: