9.When calling the removemethod with an argument if there are multiple entriesa. exactly which occurrence removed is unspecifiedb. only one occurrence is removed c. the first occurrence is removed d. all of the above 20.The most efficient approach todealing with a gap left in an array after removing an entry from a bag is toa. replace the entry being removed with the last entry in the array and replace the last entry with null b. replace the entry being removed with the first entry in the array and replace the first entry with nullc. shift subsequent entries and replace the duplicate reference to the last entry with nulld. replace the entry being removed with null