I know that tactile localization is the ability to determine which portion of the skin has been touched. The question asks, does the ability to localize the stimulus improve the more trials that are performed?

I answered yes, but I don't know how to support my answer. please help me.

An experiment of your own is generally a reliable way to support or disprove your hypothesis, but if you don't have time or resources for it you could search for similar experiments or Google to see if there's anything written about our ability to locate stimuli improves with experience.