Question

read the passage
the human brain is constantly growing and changing. when you learn something new, your brain forms new connections between nerve cells. it is like building new roads in a city to make traffic run more smoothly. then, when you practice something you have already learned, like a different language or a musical instrument, those connections in your brain become even stronger. this is similar to sealing a road so that it does not crack even as it is used more. your brain also learns and adapts when you face challenges and make mistakes. this helps you get better at skills that are hard to master.
based on the passage, how does repeating an activity affect nerve cells in the brain?
repeating an activity builds a completely new connection between nerve cells.
repeating an activity strengthens the connection between nerve cells.
repeating an activity causes the connection between nerve cells to become smooth.
repeating an activity damages nerve cells, causing you to make mistakes.

Explanation:

1. Analyze the first option: The passage says new connections are formed when learning something new, not when repeating an activity. So this is incorrect.
2. Analyze the second option: The passage states "when you practice something you have already learned... those connections in your brain become even stronger". This matches the option.
3. Analyze the third option: The passage compares building new roads (new connections) to making traffic smooth, not the connection becoming smooth from repetition. So this is incorrect.
4. Analyze the fourth option: The passage says the brain learns from challenges and mistakes, not that repetition damages nerve cells. So this is incorrect.

Answer:

B. Repeating an activity strengthens the connection between nerve cells.