The example of proactive interference means that Sheila’s ability to remember her new address is being affected by her memories of her old address.
Step-by-step explanation:
It happens because she may be living there for a long and that’s why she is so connected to the address. So when we are living somewhere for several of years then we actually get habitual of it. This is actually very normal because both adapting and leaving any habit will take some time because it is practically impossible to forget something in a blink of eye or in a sudden.
So that’s the reason that she gives the old address instead of the new one to the delivery person. This happens because she is habitual of using her old address in stuff like that not of this new address.