On the day leslie is to present his oral presentation, he wakes up with a painful strained back muscle. during the presentation, he felt no pain in his back. not until 20 minutes after the presentation is over does leslie become aware of his strained back again. leslie's occurrence is best explained by:

Leslie is so focused on her presentation that her brain diverted attention from the pain.

Explanation:

When we are in a lot of pain we can do some tricks to trick the brain into diverting the pain's attention to something else. This way our brain is "distracted" and we feel no pain.

One way to do this is by directing the senses to some activity. In Leslie's case, during the presentation, she stopped thinking about the pain and focused solely on her presentation. This made her brain divert the pain's attention to the presentation and the result was that during this period Leslie felt no pain.

answer; i believe its called ; checks   and balances;