Answer:
Fail to notice the older woman's problem.
Explanation:
As Arlette walks through a shopping mall, she happens to pass an older woman who is sitting on a bench, clutching her arm and moaning in pain. The presence of many other shoppers in the mall will most likely increase the probability that Arlette will fail to notice the older woman's problem. As there are many people in the shopping mall, and the chances are very much less that Arlette can notice someone sitting in some suffering there because there will be much noise and other noticing clues and information which will not allow her to notice that older woman there. Loads of other information and people's presence will distort her observing particularly that older woman there, if there were not many people then chances could be higher that she could have noticed the older woman's problem.
